The State Department confirmed that it was looking into reports that an Iranian-American citizen had been arrested in Iran. The news comes amid renewed tensions between Iran, which has long used Western detainees for leverage, and the United States, Israel’s biggest ally, following Israeli airstrikes on Iran last month.

“We are aware of reports that this dual U.S.-Iranian citizen has been arrested in Iran,” a State Department spokesperson wrote on Sunday in an email in response to questions from The New York Times about Reza Valizadeh, an Iranian-American journalist who rights groups said last month had been arrested and was being held in a Tehran prison without access to a lawyer. The State Department did not respond to a follow-up email asking if Mr. Valizadeh was the dual citizen being detained.

The reports come amid increasingly heated rhetoric from Iranian leaders in the past few days, after the country’s leadership initially tried to minimize the effectiveness of the Israeli strikes on Iranian air-defense systems last month. On Saturday, Ayatollah Ali Khamenei, Iran’s supreme leader, threatened a “crushing response” to Israel and the United States.

They also coincide with the 45th anniversary of the hostage crisis, when Iranians stormed the U.S. embassy in Tehran on Nov. 4, 1979, in response to perceived U.S. meddling in the country’s politics, and held more than 50 Americans as hostages for 444 days.

Rights groups said last month that Mr. Valizadeh was arrested around September and was being detained in Evin Prison, one of Iran’s most notorious detention centers.

Mr. Valizadeh once worked for Radio Farda, a Persian-language outlet that is part of Radio Free Europe/Radio Liberty, which is funded by the U.S. government. He left the organization in November 2022, RFE/RL said in a text message to The Times on Sunday.

“We have had no official confirmation of the charges against him,” said the media organization, which confirmed his detention.

Iran’s foreign ministry, its permanent mission to the United Nations in New York and its permanent mission to the U.N. in Geneva did not respond to requests for comment on Sunday.

Detained foreigners and dual citizens have long been pawns at the heart of Iran’s foreign policy: The country arrests them on fabricated allegations, often of espionage or other political crimes, and then uses them to extract concessions, like money or the release of imprisoned Iranians, from Western countries.

In June, Sweden and Iran exchanged prisoners, prompting celebrations and also concerns that the swap could validate Iran’s strategy. Last September, Iran allowed five detained Iranian Americans to leave, in exchange for five imprisoned Iranians and the unfreezing of $6 billion in Iranian oil revenue.

“Iran routinely imprisons U.S. citizens and other countries’ citizens unjustly for political purposes,” the State Department said. It called the practice “cruel and contrary to international law.”

The State Department tells American citizens not to travel to Iran “for any reason” because of the risk of “kidnapping, arbitrary arrest of U.S. citizens and wrongful detentions.”

Iranian journalists — even those who are living abroad — are frequent targets of the government’s efforts to intimidate and silence independent news coverage.

Iran ranked 176th out of the 180 countries listed on the Reporters Without Borders press freedom index this year. The group said it was “one of the world’s biggest jailers of journalists.”

Mr. Valizadeh, who had been living in the United States, traveled to Iran in February, where he was detained and questioned at the airport by Iranian intelligence officials and members of the country’s security forces, the Committee to Protect Journalists said last month. He was conditionally released, it added. He was then rearrested, according to the committee and a statement last month from HRANA, an Iranian human rights organization, but charges have not yet been disclosed.

The committee said it had not been able to confirm reports that Mr. Valizadeh faced “charges of collaborating with Persian-language media outlets abroad.” It called on Iran to release him and drop any such charges.

“Iranian journalists working and living abroad should be free to visit their homeland without fear of prosecution for their profession,” Yeganeh Rezaian, the interim Middle East and North Africa program coordinator for the committee, said in a statement last month.

In August, Mr. Valizadeh posted on X that he had returned to Iran in March, according to The Associated Press’s translation, “without any security guarantee, even a verbal one.” He has not posted to X since.

Cassandra Vinograd contributed reporting.

The Ukrainian military is losing ground in eastern Ukraine at the fastest pace in years. An influx of several thousand North Korean soldiers to Russia has added an unpredictable new dimension to the most savage war in Europe in generations.

And Russian bombardments — including 20 nights of drone assaults on the capital, Kyiv, in October alone — add to the civilian casualty count every day.

Against this difficult backdrop, Ukraine is bracing for the U.S. elections on Tuesday that will almost certainly shape the course of the country in profoundly different ways, depending on who wins the White House.

Former President Donald J. Trump, the Republican nominee, and Vice President Kamala Harris, the Democratic nominee, have expressed starkly contrasting visions for America’s role in the war as well as in the NATO military alliance that has long served as a shield against Russian aggression.

Ukrainian officials — desperate to steer clear of the toxic partisan battles that could jeopardize support from their chief military backer — are seeking to find ways to make different arguments that might appeal to both camps.

Mr. Trump’s claim that he will be able to broker a deal to end the war even before he takes office along with his often-expressed dim views of Ukraine — he has even blamed President Volodymyr Zelensky for starting the war — have stoked concerns that he would force the Ukrainians into a bad deal by cutting off military support.

Mr. Zelensky, who is asked about the prospect of a Trump victory in nearly every news conference and media appearance, told journalists in Iceland last week that he “understands all the risks.”

“Trump talks a lot, but I didn’t hear him say he would reduce support for Ukraine,” he said.

At the same time, Mr. Zelensky is under no illusions about the dire consequences of losing U.S. military assistance.

“If that support weakens, Russia will seize more territory, it would prevent us from winning this war,” he told the South Korean broadcaster KBS. “That is the reality.”

Kyiv is clearly looking for ways to appeal to Mr. Trump’s well-documented transactional approach to foreign policy, with Mr. Zelensky emphasizing that helping defend Ukraine is in America’s economic interests since his country “is rich in natural resources, including critical metals worth trillions of U.S. dollars.”

In 2022, the Canadian consulting company SecDev estimated the full value of all mineral resources of Ukraine at $26 trillion, including coal, gas and oil. Strategic resources — including some 7 percent of the world’s titanium reserves, 20 percent of its graphite reserves and 500,000 tons of lithium essential for electric car batteries — are within Ukrainian territory.

Russia is already plundering some of these resources in occupied territories, according to Ukrainian officials, British intelligence and independent investigations.

Those precious resources, Mr. Zelensky said, “will strengthen either Russia and its allies or Ukraine and the democratic world.”

Senator Lindsey Graham, Republican of South Carolina and a Trump ally, made a similar point in a video he recorded with Mr. Zelensky in September. “They’re sitting on a trillion dollars’ worth of minerals that could be good to our economy,” Mr. Graham said. “So I want to keep helping our friends in Ukraine.”

Mr. Zelensky has also mentioned the possibility of using Ukrainian units to replace certain American troops stationed in Europe after the war, noting that battle-hardened Ukrainian troops could prove useful in protecting the European continent.

That may also have been an appeal to Mr. Trump’s longstanding goal of reducing America’s military presence in Europe. In 2020, he withdrew nearly 10,000 troops from Germany — about a quarter of the contingent stationed there.

“Donald Trump is entirely unpredictable — in both negative and positive ways,” said Oleksandr Kovalenko, a prominent Ukrainian military and political analyst. “Trump could very unpredictably take a stance that completely blocks aid to Ukraine, or he could just as unpredictably decide to provide Ukraine with support that neither Joseph Biden nor Kamala Harris would ever consider.”

Ms. Harris is widely seen as more predictable and likely to pursue policies similar to the Biden administration’s, which presents a different set of challenges for Kyiv.

Many Ukrainians believe that the Biden administration has been cowed by fear of a direct confrontation with Moscow, leading to an overly cautious and slow response that ultimately consigns them to a slow defeat.

“A future President Harris would need to deal with a central problem in America’s support for Ukraine: Does it want Ukraine to beat Russia and is it willing to provide the military, diplomatic and financial resources to do so?” Mick Ryan, a retired Australian Army major general and a fellow at the Lowy Institute, a research group, wrote recently.

“If the answer to this question is yes, it will require the United States and NATO to shift their strategy, and will demand a closer alignment of NATO and Ukrainian strategy to see the war through to victory,” he wrote.

Mr. Biden’s tepid response to a plan for victory that Mr. Zelensky presented on a recent trip to Washington has added to a deepening sense of frustration that has spilled into public view, with Kyiv saying it limits its options for finding an acceptable end to the war.

There is no indication that the United States will provide Ukraine with the kind of military support it believes it needs to force Russia into negotiations and no sign that Washington is ready to commit to the kind of security guarantees Kyiv views as essential to a durable peace.

Mr. Zelensky told reporters this week that America had delivered only a small fraction of the military support it pledged in a $61 billion aid package passed in April, complicating Ukraine’s ability to plan for what comes after the presidential election in the United States.

“You have to count on very specific things in very concrete time, otherwise you can’t manage this situation, you cannot manage defending lines, you can’t secure people, you can’t prepare for the winter,” he said this week.

“It’s not a question of money,” he said. “It’s always a question of bureaucracy, logistics, ideas or skepticism.”

As Ukraine continues to lose ground on the eastern front, Mr. Kovalenko, the military analyst, said that no matter who wins on Tuesday, the domestic partisan political battles that could follow the election present their own risk, sowing chaos that Moscow will move to eagerly exploit.

“What actually frightens me more is not January 2025, when the inauguration will take place, but the period right after the election,” he said in an interview. “Russia will now take full advantage of the U.S. elections, after which internal political events will dominate, distracting American society from Ukraine and other foreign policy issues.”

Constant Méheut and Liubov Sholudko contributed reporting from Kyiv.

In the months since Canada and the United States accused India of carrying out assassination plots against Sikh separatist leaders on North American soil, a lingering question has hung over the accusations: Why would the Indian government take such a risk?

Inside India, the Sikh cause to carve out a land called Khalistan from the state of Punjab largely fizzled out decades ago. Yet the Indian government still frames the Khalistan movement as a threat to national security — for reasons more mundane but no easier to weed out.

India has repeatedly accused Khalistan-related activists in countries like Pakistan and, more recently, Canada of sponsoring gang warfare, drug trafficking and extortion in India. Proceeds from these crimes, according to India’s government, sustain a campaign of what Indian officials call terrorism in the name of a religious political movement.

“The government of India has sought to project the threat as a wider national security issue, casting a number of domestic political issues in Punjab within the framework of ‘terrorism,’” said Ajai Sahni, the executive director of the Institute for Conflict Management in New Delhi.

But Mr. Sahni and other independent security analysts said that international gangs, guns for hire and other criminals are indeed a problem in Punjab, where the Sikh religious community makes up a majority of the population.

While there are legitimate believers in the cause of a Sikh homeland, criminals have “opportunistically aligned themselves to the Khalistan cause, because in some sense it ennobles them in the eyes of people to be seen as political activists rather than criminals,” he added.

The Indian government defines terrorism broadly, to include any actions it sees as imperiling the country’s security by sowing discord or instability. India has long taken a no-holds-barred approach to stamping out movements it considers a terrorist threat, including the Khalistan cause, as well as left-wing and Indigenous insurgencies.

“The threat of terrorism is used to exploit fear and justify the suppression and silencing of minorities,” said Gunisha Kaur, a medical director of the Weill Cornell Center for Human Rights.

India has long targeted Sikhs with “impunity,” leading some to call for an independent state, said Ms. Kaur, who has written about the subject. But Sikhs, one of India’s religious minorities, hold diverse views on their ties to India, she added, which are often lost in the Indian government’s singular approach to anything it deems anti-national.

In recent years, Prime Minister Narendra Modi has led the charge in portraying the Khalistan threat as a national security matter, analysts say. He has done this, analysts say, to burnish his image as a strongman protecting his country — or, more precisely, a Hindu nationalist leader protecting the Hindu majority.

India has forcefully rejected Canada’s accusation that Indian agents killed a Canadian Sikh nationalist leader, Hardeep Singh Nijjar, on Canadian soil.

But on Tuesday, a top Canadian official said in Parliament that a campaign to intimidate, harass and even kill Sikh separatists in Canada could be traced to the highest levels of the Indian government.

The official said he had confirmed to The Washington Post that the Canadian government believed that the campaign was ordered by Amit Shah, who leads India’s Ministry of Home Affairs and is Mr. Modi’s right-hand man. The official did not say what evidence Canada had.

The Indian government has conveyed to Canadian officials that it “protests in the strongest terms to the absurd and baseless references” made to Mr. Shah, a spokesman for India’s external affairs ministry said Saturday.

Last month, Canadian officials said that several Indian diplomats in Canada were agents of India’s foreign intelligence agency, the Research and Analysis Wing, or RAW, and ran the campaign of intimidation and violence. Canada expelled six diplomats, and India responded in kind.

India’s government has been much quieter as the United States has pursued a similar case involving a foiled assassination attempt against a Sikh separatist named Gurpatwant Singh Pannun. The U.S. government has charged an Indian citizen who it says was a RAW agent, accusing him of directing the plot.

“India’s attempt on my life on U.S. soil represents a brazen act of transnational terrorism,” Mr. Pannun said in a statement. “It’s a stark reminder that while pro-Khalistan Sikhs believe in ballots, India’s government resorts to bullets.”

The Canadian and U.S. cases have provided the push for an independent Khalistan more attention than it would otherwise get, given that it is largely driven by a small part of the Sikh diaspora, Mr. Sahni, the counterterrorism expert, said.

In the past, Sikhs in Punjab have demanded a homeland alongside Muslim-majority Pakistan and Hindu-majority India, calling it a matter of justice.

The separatist cause peaked in the 1980s. In 1984, Sikh militants occupied the Golden Temple in Punjab, one of Sikhism’s holiest sites, prompting a bloody operation by Indian government forces to remove them. Five months later, Sikh bodyguards assassinated Prime Minister Indira Gandhi in revenge.

Although Sikh militancy in India was stamped out by the 1990s, a separatist movement remained in pockets around the world. Canada is among the countries where many Khalistan supporters have found a home, and India has angrily accused the Canadian government of allowing Sikh extremists and alleged criminals to operate freely from inside its territory.

On Tuesday, Canada’s ambassador to India, Cameron MacKay, told The New York Times that Canada was “not in a position to arrest people simply because they support a separatist movement in a foreign country,” citing its expansive protections for freedom of speech. “I know that the Indian government sees things very differently and wishes that we that we would do so, but we’re not going to,” Mr. MacKay added. “It’s simply not provided for in Canadian law.”

While it is India’s foreign intelligence agency that has been linked by Canada and the United States to assassination plots, India’s National Investigation Agency — a domestic counterterrorism law enforcement agency — has also long focused on Khalistan figures.

The agency is part of the Ministry of Home Affairs, led by Mr. Shah, Mr. Modi’s close ally. It has described Khalistan separatists as operating within a “terrorist-gangster-drug smuggler nexus.”

The case of Lakhbir Singh Sandhu illustrates India’s anti-Khalistan efforts. Mr. Sandhu, whom the Indian government has labeled a terrorist, is wanted in connection with several Khalistan-allied outfits accused by the National Investigation Agency of conspiring to “wage war against the country.” In January 2023, the agency offered a reward of about $18,000 to anyone providing information on Mr. Sandhu.

In July of this year, the agency said it had arrested an aide to Mr. Sandhu, accusing him of supplying weapons in Punjab for extortion and other “large-scale terror activities.” The criminal acts, the agency said, were “part of the larger conspiracy of various banned Khalistani terrorist organizations to destabilize India by unleashing violent acts in Punjab and other places.”

The Indian government has also disclosed that Mr. Sandhu is on a list that India provided to the Canadian authorities of people it wants extradited. He remains at large.

Mr. Nijjar, the Sikh leader killed in Canada, who was also on India’s terrorist list, was accused of directing extortion schemes and other gang-related activities.

Another factor that makes Sikh separatism a sensitive issue is its connection to Pakistan, India’s archnemesis. Pakistan has aided the Khalistan movement as a way to seed instability in India, analysts say. Some see the presence of pro-Khalistan groups like Babbar Khalsa International, banned in India but with members in Pakistan, as part of a Pakistani strategy known informally in the counterterrorism community as “death by a thousand cuts.”

“Khalistanis have a very robust relationship with Pakistani terrorism,” said Abhinav Pandya, an expert on counterterrorism policy. Mr. Pandya said that although the drug trade on either side of the India-Pakistan border was long established, “in recent years, it has become deeply integrated with the terror network.”

While the Khalistan cause is largely seen in India as a fringe movement with ties to the drug trade, there is some concern among Indian state and federal officials about so-called radicalization of Punjabi youths.

Punjab was once among India’s most prosperous states. But the remnants of the 1980s conflict, combined with failed economic policies and shrinking job opportunities, have unleashed a slow-burning crisis in the state.

Widespread drug addiction is one of the biggest challenges. Although Punjab is listed as India’s 15th-largest state, it accounts for the third-highest number of drug-related cases, according to government officials.

In such a tinderbox, the Khalistan movement could find more fertile ground among vulnerable and jobless young men, analysts said.

Lakhwinder Singh, a visiting professor of economics at the Institute for Human Development in New Delhi, said that generations of Punjabis had left the state, driven by “distress or hopelessness.”

“If youth is not provided adequate employment opportunities, there is a likely possibility that youth can be engaged in social upheavals,” Mr. Singh said. “During the ’80s, the youth in Punjab picked up arms and, nowadays, are attracted toward using intoxicants.”

Matina Stevis-Gridneff contributed reporting from Toronto.

When a state-funded Polish radio station canceled a weekly show featuring interviews with theater directors and writers, the host of the program went quietly, resigned to media industry realities of cost-cutting and shifting tastes away from highbrow culture.

But his resignation turned to fury in late October after his former employer, Off Radio Krakow, aired what it billed as a “unique interview” with an icon of Polish culture, Wislawa Szymborska, the winner of the 1996 Nobel Prize for Literature.

The terminated radio host, Lukasz Zaleski, said he would have invited Ms. Szymborska on his morning show himself, but never did for a simple reason: She died in 2012.

The station used artificial intelligence to generate the recent interview — a dramatic and, to many, outrageous example of technology replacing humans, even dead ones.

Mr. Zaleski conceded that the computer-generated version of the poet’s distinctive voice was convincing. “It was very, very good,” he said, but “I went to her funeral, so I know for sure that she is dead.”

The technology-enabled resurrection of the dead poet was part of a novel experiment by Off Radio Krakow, an arm of Poland’s public broadcasting system in the southern city of Krakow. The aim was to test whether A.I. could revive a moribund local station that had “close to zero” listeners, according to the head of public radio in Krakow.

The station also planned from-the-grave interviews with other dead people, including Jozef Pilsudski, Poland’s leader when it regained its independence in 1918.

Novelty value — and a storm of public outrage — worked to bolster Off Radio Krakow’s audience, which the head of Radio Krakow said grew to 8,000 overnight from just a handful of people after the introduction of three A.I.-generated Generation Z presenters — Emilia, 20, Jakub, 22, and Alex, 23, each of whom had a computer-generated photograph and biography on the station’s website.

Less welcome than the audience surge, however, has been a barrage of abuse directed at the public broadcasting system and accusations that it was sacrificing humans on the altar of technology.

“I have been turned into a job-killing monster who wants to replace real people with avatars,” said Mariusz Marcin Pulit, the editor in chief of Radio Krakow and of niche stations operating under its umbrella, like Off Radio Krakow.

He insisted that it was never his intention to replace people with machines, and that his only goal was to revive Off Radio Krakow, make it more appealing to younger listeners and stir debate about A.I. as Poland’s Parliament discusses new legislation to regulate its use.

The technology used to generate the fake interview with Ms. Szymborska and other programing, he added, has been widely used: Open AI’s ChatGPT, speech synthesis software developed by ElevenLabs, and the image-generating programs of Leonardo.Ai.

But his assurances have done nothing to calm public anger — and alarm that humans are being written out of the script.

Among those outraged by Mr. Pulit’s experiment was Jaroslaw Juszkiewicz, a radio journalist whose voice was used for more than a decade to guide drivers using the Polish version of Google Maps. His replacement by a metallic computer-generated voice in 2020 stirred fury on social media, prompting Google to restore Mr. Juszkiewicz, at least for a time.

He announced recently that he had been yanked again, lamenting that A.I. was “sweeping through the world of human voice work like a giant steamroller. And I can, in my own human voice, say, probably for the last time: ‘Smile beautifully and head south.’”

In a Facebook post, he said the use of A.I. to fake an interview with the dead Nobel Prize winner had left him speechless. “If that is not a breach of journalistic ethics,” he said, “I don’t know what is.”

The National Radio and Television Council, a regulatory body stacked with supporters of Poland’s previous right-wing government, assailed Mr. Pulit, who was appointed by a new center-left administration formed in December. He was “eliminating the human factor” and forcing media to obey “unethical commands and ideas serving, for example, strictly political interests,” a council member, Marzena Paczuska, wrote in a letter to the culture minister.

A member of the government also expressed alarm. The minister of digitalization, Krzysztof Gawkowski, complained on the social media platform X that “although I am a fan of A.I. development, I believe that certain boundaries are being crossed more and more.” He added: “The widespread use of A.I. must be done for people, not against them!”

Tired of being accused of wanting to make humans redundant, Mr. Pulit, the head of Radio Krakow, recently pulled the plug on his A.I. experiment.

“We are pioneers, and the fate of pioneers can be difficult,” he said in a recent message to staff members announcing an abrupt termination of A.I. presenters and their replacement by music created and performed by humans.

Among the A.I. presenters removed from Off Radio Krakow was Alex Szulc, a nonexistent person who had been presented as a nonbinary progressive “full of social commitment.” A biography on the station’s website was later rewritten to delete any mention of the presenter’s sexual orientation after angry complaints from L.G.B.T.Q. activists that they needed a real person to speak for them, not a computer-generated one.

Also gone is Emilia Nowak, the station’s computer-generated “pop culture expert,” who conducted the “interview” with the dead poet. The station first announced the conversation as if it were a real interview, but later clarified that it had been fabricated by a machine.

Michal Rusinek, the head of a foundation that manages the late Nobel Prize winner’s literary estate, said he had given Off Radio Krakow permission to use Ms. Szymborska’s voice for the segment because the poet “had a sense of humor and would have found it funny.”

But he said the interview “was horrible” and put words in the poet’s mouth that she would never have used, making her sound “bland,” “naïve” and of “no interest whatsoever.” But that, he added, was heartening because “it shows that A.I. does not yet work” as well as humans. “If the interview had been really good,” he said, “it would be terrifying.”

Felix Simon, the author of a report published in February on the effect of A.I. on journalism, said the Polish experiment had not altered his view that technology “aids news workers rather than replaces them.” For the moment, he added, “there is still reason to believe it will not bring the big jobs wipeout some people fear.”

For the many in Poland who criticize Off Radio Krakow’s flirtation with A.I., the station’s use of computer-generated presenters, though now suspended, has highlighted a grave and immediate danger.

An online petition drafted by Mr. Zaleski, the terminated culture show host, and Mateusz Demski, a fellow presenter who also lost his job, warned that “the case of Off Radio Krakow is an important reminder for the entire industry” and a “dangerous precedent that hits us all.”

The use of A.I.-generated presenters, the petition warned, “is opening the door to a world in which experienced employees associated for years with the media and people employed in creative industries will be replaced by machines.”

Mr. Pulit, the editor in chief, dismissed that as “fake news,” noting that none of the people who had lost their jobs at the radio were full-time employees.

Mr. Zaleski said most of his income had always come from work as a theater director, so he was not particularly upset when he lost his weekly slot on Off Radio Krakow, which paid only $62 per show.

But he said he was appalled at being replaced by a machine-generated substitute. “I was very angry that real, deep talks and real interviews with real people were replaced with something totally fake.”

Anatol Magdziarz contributed reporting from Warsaw.

The patrol begins at dusk every night, as the thuds from nearby artillery echo over the distant hills in southern Lebanon. Some scouts settle into hidden perches on the outskirts of town, keeping close watch on the roads leading into it. Others hop on their motorcycles and roam the streets, alerting the police to any suspicious cars or strangers.

The volunteer force describes itself as the first line of defense in Hasbayya, a mostly Druse and Christian town near the Lebanese-Israeli border. But the volunteers are not scanning for only the Israeli troops who invaded southern Lebanon last month as the conflict between Hezbollah and Israel escalated. They are also trying to prevent Hezbollah fighters from entering the town — and dragging it into the wider war.

The Israel-Hezbollah conflict was once contained to the border region, but has since enveloped swaths of southern and eastern Lebanon, a small Mediterranean country half the size of Vermont. Israeli airstrikes have rained down across the region, leveling beige stone homes and pulverizing villages into rubble. Hezbollah fighters have volleyed rockets back toward Israel and clashed with invading Israeli troops.

Israel’s military campaign has left few communities in the south untouched. Villages in the south where there is deep support for Hezbollah, an Iran-backed Shiite Muslim movement, have been flattened. Other mostly Christian, Sunni and Druse Lebanese towns that do not support Hezbollah have also been hit.

Lebanon has long been deeply divided along sectarian lines, mainly among its three dominant groups — Shiite and Sunni Muslims and Christians. Hezbollah is the most powerful political and military group in the country, representing many Shiites.

While Lebanese people are largely united against Israel’s onslaught, some in southern towns where Hezbollah does not hold sway say they feel trapped in the crossfire between Israel’s firepower and Hezbollah’s fighters. Desperate to shield their communities, some are cobbling together informal defenses of their own.

In Hasbayya, residents have established a neighborhood watch group. Some local leaders have negotiated with Hezbollah to keep its fighters from launching rockets from the town.

Officials within Hasbayya have also turned away Shiite Muslim families displaced from nearby villages where Hezbollah is dominant — a move that risks inflaming sectarian tensions that are always simmering. Local officials said they feared that Hezbollah fighters might be among the families, which could make them — and by extension the town — a target of Israeli strikes.

Locals know that Hezbollah, with its overwhelming military might, could go back on their pledge to steer clear of Hasbayya at any time and the town would be largely powerless to stop them. But for now, Hezbollah is treading lightly to maintain some good will with other sects and religious communities — and Hasbayya residents are doing what they can to deter the group.

“We don’t want any strangers or anyone related to Hezbollah here,” said Ghassan Halabi, the deputy mayor of Hasbayya, told visiting New York Times journalists last month. “It took us years to build this town and it could all be destroyed within minutes. We can’t allow that to happen.”

Sprawled across the foothills of Mount Hermon, Hasbayya is only six miles from the Israeli border. Winding roads connect clusters of houses and thickets of olive and pine trees, as well as ancient ruins dating back to the Crusader period. The town is home to about 30,000 people, mostly Druse Lebanese — adherents to a 1,000-year-old religion — as well as Christians and some Sunni Muslims.

These days, Hasbayya is cloaked in the din of war raging around it: The booms of artillery shells, the buzz of drones and the screech of Israeli jets overhead. When airstrikes hit in the distance, plumes of smoke curl into the air along the green slopes of mountains.

When Hezbollah began launching rockets into Israel last year in support of Hamas, prompting months of tit-for-tat strikes, local leaders in Hasbayya and other nearby Christian and Sunni villages approached Hezbollah officials in the area with a request.

We asked them “not to launch rockets from inside the town,” said Wissam Sliqqa, a Druse sheikh and local leader in Hasbayya. “We wanted to preserve the safety of our residents and ensure they could remain in their homes” and not be forced to flee north, he explained.

Hezbollah leaders agreed. But when the war intensified and Israeli airstrikes began pummeling villages on the edge of Hasbayya, panic took hold.

Worried that Hezbollah fighters might fall back to Hasbayya, dozens of residents volunteered with the municipality police to work shifts on a new neighborhood watch. They created a WhatsApp group for people in nearby villages to flag anything suspicious. The mayor, Abu Nassar, imposed an 8 p.m. curfew, after which all residents must remain inside their homes. After midnight, no cars are allowed to enter or drive through Hasbayya.

Those efforts are trying to fill the void left by the Lebanese National Army, which has never been strong enough to defend the country against invaders. Local officials know that their ragtag efforts can do little to protect Hasbayya against Israeli ground troops or airstrikes. But they hope the scouts can prevent Hezbollah fighters from setting up positions within the town. They can also alert residents in time to flee if Israeli troops do move forward.

“We’re worried,” said Kanj Nawfal, a municipal police officer who oversees the volunteer guards. “We are trying to be careful but if something happens,” he added, his voice trailing off. He wrung his hands, searching for the right words.

“This war is bigger than us,” Mr. Nawfal explained.

The town’s fears are rooted in the wreckage of nearby villages, damaged as the wake of destruction in Israel’s fight against Hezbollah has widened. In recent weeks, hundreds of people fleeing nearby villages flooded into Hasbayya looking for refuge.

Mohammad Fares, 34, arrived in late September from Chebaa, a mostly Sunni town wedged between Hasbayya and the Israeli border. The town had mostly been insulated from the strikes until late September when, around 2:30 one morning, an Israeli airstrike crashed into his neighborhood and killed a family of nine, according to residents.

Hours later, another airstrike landed in the town. Mr. Fares and his neighbors clambered into cars — some carrying more than a dozen people — and sped toward Hasbayya.

“It was like nowhere is safe anymore,” Mr. Fares said.

Mr. Fares, who is Sunni, found refuge in Kfeir, a village in greater Hasbayya, in a high school that was hastily converted into a shelter. In the days that followed, other families fleeing Marjayoun, a Christian city to the east, flocked to the school too. But local officials closed the doors when Shiite Muslim families leaving villages that are known to have deep-seated support for Hezbollah arrived.

“Families came and we told them, respectfully, there is no more space in our shelters,” said Mr. Halabi, the deputy mayor.

Mr. Halabi’s misgivings reflect the evolving pattern of Israeli airstrikes that have moved from solely Shiite pockets of Lebanon to also include areas home to mostly Christian, Sunni Muslim and Druse Lebanese, which were once considered safe. While many shelters in other towns have offered refuge to people of all religious backgrounds, strikes on houses and apartments hosting displaced families have stirred fears in Hasbayya that Hezbollah fighters are blending in with refugees, prompting Israel to strike them.

The limits of efforts to keep the town safe were made real last month: An Israeli airstrike leveled a guesthouse in the town, killing three journalists from Lebanese news outlets either owned by or seen as sympathetic to Hezbollah. It was the first strike within the town limits since the war escalated — and stoked fears that it was no longer off-limits.

“We don’t have problems with anyone, we don’t have outgoing rockets, we just want stability,” said Nayef el Hassaniyeh, 59, as he stood on his rooftop on the southern edge of the town one recent afternoon.

From his perch overlooking the mountains, Mr. Hassaniyeh patiently scanned the escarpments across from him. Almost every night since the conflict escalated, the spine of the mountains in the distance light up with the flash of airstrikes — a real-time map of the war’s path.

Mr. Hassaniyeh and some of his neighbors fear the strikes in the Sunni and Christian towns in the distance foreshadow Hasbayya’s fate if the war drags on. If cities where Hezbollah does not have support could be hit, they wonder, what is to stop Israeli airstrikes from raining down on theirs as well?

“This war has been imposed on us. Did we choose it as Lebanese? No. They imposed it on us,” Mr. Hassaniyeh said, referring to Hezbollah. “We just want to protect ourselves. We just want peace.”

Iran’s supreme leader on Saturday threatened “a crushing response” to Israeli strikes on his country, as the Pentagon said it would deploy additional resources to the region in the coming months.

Tehran initially appeared to play down the damage caused by Israeli strikes inside Iran late last month, raising hopes that it might de-escalate the situation rather than pursue a new cycle of retaliation. But in recent days, Iranian officials have changed their tone.

Iran’s supreme leader, Ayatollah Ali Khamenei, has the authority as commander in chief to order strikes on Israel. In a statement posted online, he said on Saturday that Israel and the United States would “definitely receive a crushing response” for actions against Iran.

His remarks echoed two Iranian officials who this past week said that Iran would retaliate, with one telling state news media that a response would be “definite” and a second saying Iran would launch “a fierce, tooth-breaking” response.

After years of avoiding direct military clashes, Iran and Israel have been locked in an escalating monthslong cycle of retaliation that has drawn in their allies and proxies, bringing the region to the brink of an all-out war.

The Pentagon in late September extended the deployment of an aircraft carrier strike group in the Gulf of Oman to deter Iranian attacks and shoot down any ballistic missiles fired into Israel.

To maintain those kinds of capabilities in the region when that carrier, the U.S.S. Abraham Lincoln, returns to its home port, the Pentagon announced late Friday that a new deployment of ships and land-based warplanes would head to the region.

Maj. Gen. Pat Ryder, the Pentagon press secretary, said that Defense Secretary Lloyd J. Austin III had ordered the deployment of fighter aircraft, ballistic missile defense destroyers and B-52 long-range bombers to assist in the defense of Israel and other U.S. interests in the region.

“Secretary Austin continues to make clear that should Iran, its partners, or its proxies use this moment to target American personnel or interests in the region, the United States will take every measure necessary to defend our people,” General Ryder said in a statement.

The United States has already bolstered its military presence in the region as tensions rise. It sent an advanced missile defense system, called the Terminal High Altitude Area Defense system, or THAAD, and the 100 American troops needed to operate it, to Israel.

Their arrival less than two weeks ago was the first time that U.S. troops had been deployed to Israel for such a mission since the start of the war last October.

The Biden administration sent key envoys, including the C.I.A. director, to the Middle East this week in hopes of generating some momentum in talks to end Israel’s war against Hamas in Gaza and its spiraling conflict with Hezbollah in Lebanon. Both groups are Iranian proxies. But those efforts have floundered, and the fighting has continued unabated.

On Saturday, Lebanon’s health ministry said that one person had been killed and 15 others had been wounded by an Israeli airstrike in the Dahiya, a densely populated area south of Beirut where Hezbollah holds sway. The previous day, heavy Israeli strikes killed at least 52 people in the central part of the country, the Lebanese authorities said, and seven people in northern Israel were killed by Hezbollah rocket attacks.

The Israeli military said on Saturday that its forces had struck more than 120 sites in both Lebanon and Gaza since the day before, including an airstrike in the Lebanese city of Tyre that it claimed killed two Hezbollah commanders. It also said troops were conducting ground operations in northern, central and southern Gaza.

In central Israel early on Saturday, a rocket strike hit Tira, an Arab-majority town in central Israel, and injured several people. The Israeli military said that three rocket launches had been detected overnight from Lebanon, including at the region that includes Tira. Another 30 launches from Lebanon were detected on Saturday afternoon, the military said.

Magen David Adom, Israel’s emergency medical service, said 11 people were wounded in Tira, with most of the injuries minor to moderate. A photograph and a video posted by the emergency service showed the top floor of a building with its walls blown out.

Hezbollah started striking Israel in solidarity with Hamas, its ally in Gaza, after the Oct. 7 Hamas-led attacks last year prompted Israel to launch a war against the group in Gaza.

After nearly a year of cross-border attacks that primarily landed in the border region, Hezbollah in recent months has taken aim deeper inside Israel. The militant group launched missiles at the densely populated Tel Aviv area in September and October. Those were intercepted with no reported injuries or damages.

Victoria Kim, Rawan Sheikh Ahmad and John Ismay contributed reporting.

Israeli naval commandos, ferried by speedboats, captured a man Israel called a senior Hezbollah operative in a sea-and-land operation on Friday that marked the deepest known incursion yet by Israeli forces into Lebanese territory during this war.

An Israeli military official, who spoke on the condition of anonymity in line with military protocol, said the forces brought the man back to Israel for interrogation. The operation was carried out by an elite Israeli naval commando unit, Shayetet 13, which is akin to the U.S. Navy SEALs, the official added.

Most of Israel’s campaign has been limited to aerial bombardment of southern and eastern Lebanon, along with the area just south of Beirut, all strongholds of support for Iran-backed Hezbollah. Israeli ground troops, so far, have been known to operate only in the south.

The commandos landed early Friday along the Mediterranean coastline in Batroun, a city about 20 miles north of the capital, Beirut, according to Lebanon’s state-run news agency. They abducted the man, identified by Lebanese officials as a ship captain named Imad Ahmaz, from a nearby residential building before leaving by speedboats, the agency reported.

Lebanese media circulated CCTV footage on Saturday showing an individual being led away by more than a dozen armed men.

Hussen Dilbani and his wife, Rania, who lived next door in the building, said they had decided to leave the apartment after the raid, having already been displaced twice before, from southern Lebanon and then Beirut. They said they did not know whether their neighbor was a member of Hezbollah.

“I did not see their faces, just shadows and voices. They said they were from state security,” said Mr. Dilbani, recounting how the Israeli commandos had claimed to be Lebanese security forces as they broke down his neighbor’s door at around 2:30 a.m. on Friday. “I thought they came to arrest someone involved in something.”

Other residents in the building reported also being told by the Israeli commandos that they were Lebanese security officers, and said they had been ordered to stay inside their homes.

“Wherever you go, you are not safe,” Ms. Dilbani said.

Hezbollah called the incident a “Zionist aggression in the Batroun area,” but did not confirm that one of its members had been captured.

Batroun, a predominantly Christian city, is not a support base for Hezbollah, but it has been swamped in recent weeks by residents of nearby Beirut who have fled Israel’s bombing campaign.

Israel began an intensified military campaign against Hezbollah in September, nearly a year after the group began firing rockets into Israel in solidarity with Hamas in Gaza. The Israeli offensive has displaced more than a fifth of Lebanon’s population.

In previous conflicts, the Israeli military carried out commando operations deep inside Lebanon to kidnap and kill members of Hezbollah or Palestinian factions.

Ali Hamieh, Lebanon’s minister of public works and transport, said in an interview that the abducted man was a civilian ship captain taking a course at a maritime institute in Batroun, where he rented a nearby chalet.

Lebanon’s caretaker prime minister, Najib Mikati, said he had ordered the government to file a complaint to the U.N. Security Council over the abduction.

Reporting was contributed by Hwaida Saad, Dayana Iwaza and Liam Stack.