Hamas’s handbook for underground combat describes, in meticulous detail, how to navigate in darkness, move stealthily beneath Gaza and fire automatic weapons in confined spaces for maximum lethality.

Battlefield commanders were even instructed to time, down to the second, how long it took their fighters to move between various points underground.

The 2019 manual, which was seized by Israeli forces and reviewed by The New York Times, was part of a yearslong effort by Hamas, well before its Oct. 7 attack and current war with Israel, to build an underground military operation that could withstand prolonged attacks and slow down Israeli ground forces inside the darkened tunnels.

Just a year before attacking Israel, Yahya Sinwar, the leader of Hamas in the Gaza Strip, approved spending $225,000 to install blast doors to protect the militia’s tunnel network from airstrikes and ground assaults.

The approval document said that Hamas brigade commanders had reviewed the tunnels below Gaza and identified critical places underground and at the surface that needed fortification.

The records, along with interviews with experts and Israeli commanders, help explain why, nearly a year into the war, Israel has struggled to achieve its objective of dismantling Hamas.

Israeli officials spent years searching for and dismantling tunnels that Hamas could use to sneak into Israel to launch an attack. But assessing the underground network inside Gaza was not a priority, a senior Israeli official said, because an invasion and full-scale war there seemed unlikely.

All the while, officials now realize, Hamas was girding for just such a confrontation.

Were it not for the tunnels, experts say, Hamas would have stood little chance against the far superior Israeli military.

The underground-combat manual contains instructions on how to camouflage tunnel entrances, locate them with compasses or GPS, enter quickly and move efficiently.

“While moving in the dark inside the tunnel, the fighter needs night-vision goggles equipped with infrared,” the document, written in Arabic, reads. Weapons should be set to automatic and fired from the shoulder. “This type of shooting is effective because the tunnel is narrow, so the shots are aimed at the kill zones in the upper part of the human body.”

Israeli officials knew before the war that Hamas had an extensive tunnel network, but it has proved to be more sophisticated and extensive than they realized.

Early in the war, they estimated that it stretched for about 250 miles. Now they believe it is up to twice as long.

And they continue to discover new tunnels. Just last week, Israeli commandos rescued a Bedouin Arab citizen of Israel who was found alone in an underground warren. The government said on Sunday that six hostages had been found dead in another tunnel.

Mr. Sinwar, Israel’s highest-value target, has been suspected of managing the war and evading capture from a tunnel.

The records show how both sides have had to adapt their tactics in the war. Just as Israel underestimated the tunnels, Hamas prepared for subterranean battles that have not materialized. Israel was reluctant, especially early in the war, to send troops underground where they might face combat. Hamas has primarily ambushed soldiers near tunnel entrances, while avoiding direct confrontations.

That has left Hamas to use the tunnels to launch aboveground hit-and-run attacks, hide from Israeli forces and detonate explosives using remote triggers and hidden cameras, according to Israeli military officials and a review of battlefield photos and videos.

These maneuvers have slowed Israel’s assault, but its military has still decimated Hamas’s ranks, routed them from strongholds and forced them to abandon huge swaths of the tunnel network that they invested so heavily to build.

Members of the Israeli military discovered the tunnel warfare document in Gaza City’s Zeitoun District in November, officials said. A letter from Mr. Sinwar to a military commander was found that same month south of the city. The documents were made available to The Times by Israeli military officials.

A military spokesperson said that “the fact that Hamas is hiding in tunnels and managing much of the fighting from there prolongs the war.” A senior Hamas official declined to comment on the tunnel strategy.

The markings on the documents are consistent with other Hamas materials that have been made public or been examined by The Times. And Israeli soldiers have described details, like camouflaged tunnel entrances and recently installed blast doors, that are consistent with the Hamas documents. The documents also describe the use of gas detectors and night-vision goggles, equipment that Israeli forces have found inside tunnels.

“Hamas’s combat strategy is based on underground tactics,” said Tamir Hayman, a former head of Israel’s military intelligence. “This is one of the primary reasons they have managed to withstand the I.D.F. thus far.”

Since the war started, much has been revealed about the subterranean network, which has been called the “Gaza Metro.” Hamas uses some rudimentary tunnels simply to mount attacks. The fighting manual describes how people should maneuver these narrow passages in darkness: with one hand on the wall and the other on the fighter in front.

Other tunnels are sophisticated command-and-control centers or arteries connecting underground weapons factories to storage facilities — concealing Hamas’s entire military infrastructure. In some cases, Hamas has used solar panels installed on the roofs of private homes to provide power underground.

Some tunnels also serve as communication hubs. This past winter, Israeli forces discovered a Nokia telecommunications system underneath the headquarters of the U.N. agency for Palestinian refugees.

Such Nokia systems provide voice and data services, according to the manual obtained by The Times, and could have functioned as a switchboard for an underground communication network. But the features require additional hardware and it is not clear what abilities Hamas had.

Hamas has been known to hold Israeli hostages underground, so every tunnel needs to be investigated and cleared, Israeli officials say.

Destroying a tunnel section can take dozens of soldiers about 10 hours, according to a senior Israeli officer who is an expert on tunnel warfare. Last year, the Israeli Army discovered a tunnel that had a depth of 250 feet — about the height of a 25-story building. The army said it took months to destroy it.

“I cannot overstate that in any way. The tunnels impact the pace of the operations,” said Daphné Richemond-Barak, a tunnel warfare expert at Reichman University in Israel. “You can’t advance. You can’t secure the terrain.”

“You’re dealing with two wars,” she added. “One on the surface and one on the subsurface.”

One Israeli special operations officer, who, like others, spoke on the condition of anonymity because they were not authorized to publicly discuss military activities, said that as soldiers approached the tunnels, Hamas sometimes blasted the ceilings, causing cave-ins that would block the path.

An Israeli military official said that it could take years to destroy the entire tunnel network.

Israel’s military leadership has made the tunnels its main target. But the campaign has come at a steep cost for Palestinian civilians. Many of the tunnels snake beneath densely occupied areas. Israel has publicized videos of the military destroying tunnels with more than 16 tons of explosives per kilometer.

The Israeli military estimates that it costs Hamas about $300,000 to build roughly a half-mile-long rudimentary tunnel. Ms. Richemond-Barak said that the letter from Mr. Sinwar highlighted the expense and sophistication behind the effort.

The letter was written to Muhammad Deif, the group’s military commander, who is believed to have been an architect of the Oct. 7 attack. It is not clear when Hamas completed its review of tunnel fortifications or whether it was done in connection to the attack planning. Mr. Sinwar wrote that “the brigades will be given the money according to the level of importance and necessity.”

The letter could indicate where the group anticipated the toughest fighting. Mr. Sinwar authorized the most money for doors in northern Gaza and Khan Younis. Indeed, some of the heaviest fighting during the war has taken place in those areas.

“The Hamas tunnel system was an essential, if not existential element of their original battle plan,” said Ralph F. Goff, a former senior C.I.A. official who served in the Middle East.

It is not clear when Hamas started using the doors, but Ms. Richemond-Barak said the group’s heavy reliance on them was new. She was not aware of Hamas using them during a 2014 war with Israel.

Blast doors seal tunnel segments from each other and from the outside, protecting against bombings and breaches. They also hamper the army’s use of drones to inspect and map tunnels.

The Israeli military has repeatedly encountered blast doors as they cleared tunnels. Despite the tactics described in the tunnel-fighting manual, once those doors have been breached, Israeli officials say, soldiers seldom find Hamas fighters behind them. They have fled, reflecting an attack-and-retreat strategy that has become commonplace.

Eric Schmitt contributed reporting from Washington.

When the Russian invasion of Ukraine began in February 2022 and some of her students fled abroad, Iryna Kovaliova, a literature teacher, decided it was time to retire.

“I wrote my resignation letter and took my things from school,” she said. But the children in her sixth-grade class, 6H, in a Kyiv school, begged her to stay, “at least for the duration of the war,” she recounted in a recent interview.

Two years later, she is still teaching at 63, three years past the retirement age for teachers, torn by the heartbreak of watching her students grapple with the trauma of air raids, bombings and the loss of loved ones. She worries for those who have been displaced, forced to study online, as well as for former students who have already enlisted in the army and are fighting on the front lines.

She begins every morning by checking the social media accounts of two former students who are in the army, relieved when she sees they have been online, knowing that at least they are alive.

Maria Lysenko, the principal of the school, said she was worried for a whole generation of children, but also for her teachers.

“Children are like tuning forks, a reflection of what is happening in our lives,” Ms. Lysenko said. “There is a reason that a child is lying on the desk, maybe he has not slept all night, because he was waiting for news from someone close.”

“But what about the teachers?” she added. “They are holding on, no breakdowns, no panic, doing their best.”

Children and teachers across the country began their first day of classes for the new academic year on Monday at a time when Russia has been stepping up bombardments of Ukrainian cities.

Class 6H is the most troubled group of the sixth grade in Ms. Kovaliova’s school. The children, she says, dislike discipline and cannot sit still after going through lockdown during Covid and then two years of disruption with the outbreak of war.

They often ignore teachers, Ms. Kovaliova said: “It’s a difficult group.”

But, she added, she could see reasons behind their behavior.

“These children are loud. They want to shout something. But we never asked what they are shouting about,” she said.

“These children are crying for help,” she added. “They are like a bleeding wound, and no one sees it.”

So instead of checking their homework on a recent morning, she surprised the class with a sudden question. She invited a reporter from The New York Times along to listen in.

“What changed inside you in these two years?” she asked the class. “And how would you reflect it in a collective painting?”

Since the Russian invasion began, she said she had been pushing the school to consider displaying in the school’s bomb shelter a giant mural, painted by the children, in which they could express their experience of the war. The school prevaricated, so she decided to plunge ahead, asking her students to start thinking about the project.

The first to speak was Danya, 11, a student who was displaced from his home in the Ukrainian city of Luhansk in 2014, when fighting first broke out between Moscow-backed separatists and government forces in the eastern regions of Luhansk and Donetsk.

“Before, I thought of my house as a wardrobe where I could hide, where nothing worries you,” he said. “And it’s not like that.”

Then Yehor, 11, from Kyiv, said he had fled the capital with his mother at the time of the full-scale Russian invasion in February 2022.

“I wanted to stay, but my parents thought that soldiers were already approaching,” he said. “We left. My dad stayed, and he saw with his own eyes a missile flying and hitting.”

Yehor’s family fled to a town west of the capital. He kept a religious icon with him, which he thinks helped them to make the trip safely. He said he wanted to depict that icon on the painting.

Ms. Kovaliova explained her idea: “Imagine, a student comes to the school in 20 years’ time,” she told the class. “The war is over. We live in a happy country. And he sees this mural signed, ‘Class 6-H.’ He sees a wardrobe and an icon on a wardrobe. And he starts thinking.”

“What changed inside you in these two years?” she said. “And how would you reflect it in a collective painting?”

Nazariy, 12, replied, “For me, war is death, in the first place. It’s very painful.”

Nervous laughter broke out in the classroom.

“My uncle died,” he said.

Ms. Kovaliova hushed the class. “How old was he?” she asked.

“Thirty-two,” Nazariy said.

“I want to cry,” Ms. Kovaliova said. “What would you paint?” she asked him.

“A fortress. Knights entering the fortress. And a lot of blood all around,” he said.

“How were you changed?” the teacher asked, turning to the class.

“I became less ashamed to voice my opinion,” Nazar, 12, said. “Before, I was thinking: ‘Damn, why was I born in Ukraine?’ After the war started, I began to feel cool that I’m from Ukraine. I would paint a mirror on the wardrobe — to see how I changed.”

Some of the children spoke about the Ukrainian language.

“Before the war, most people spoke Russian,” said Liudmyla, 11. “And many switched to Ukrainian when the war started.”

“I would paint a lock, meaning our language was locked in a wardrobe, almost not used,” she said. “And now people understand that you need to value it, because it’s your country. It was let out.”

“I was more depressed before the war,” Makar, 11, said. “And I started to speak more Ukrainian. I would draw a shield.”

But war and violence kept crowding in on their thoughts.

“I would draw an ordinary girl in front of the mirror. And in the reflection, a girl in a military helmet,” said Maria, 11, who fled from Donetsk.

Many families have been torn apart as grandparents or other relatives were left behind and ended up on the Russian-controlled side of the front line.

Stories of personal separation and loss began to emerge.

“I didn’t appreciate my relatives, my grandma or great-grandma,” said Maria, 11, who is from the Kyiv region. “I didn’t care about spending time with them. But when my grandma and great-grandma were under occupation, I realized that they could be gone.”

“I would draw a big dome which would protect the whole painting,” she added.

Vira, 12, described running to a bomb shelter on the first day of the war as parts of a missile fell on her neighborhood in Kyiv. “I would draw a missile flying over the dome,” she said.

Liza, 11, said, “I realized I want to live.” She added: “I would draw an angel and a village with half-destroyed houses. Because Russians were in a village where we have a cottage, and now half of the village is destroyed. The angel covers the sky and rebuilds houses from the pieces.”

Arina, 11, revealed that she had been displaced from eastern Ukraine and separated from her grandparents who remained in Russian-occupied territory. She began to weep, and several of her classmates rushed to embrace her.

“I would paint a person crying,” Arina said. “Because people die, and you can’t even visit their grave.”

“It’s a very important conversation,” their teacher said. “Thank you. I understand you better. You understand each other better.”

Stories were tumbling out now.

“My brother died recently, he was 24,” a boy called Sasha said. “I didn’t value those moments of life with him. I would paint arms holding coffins.”

“Our painting is getting complicated,” he added.

Another classmate, Kyryl, spoke up.

“When the war began, it was much scarier than I expected,” he said. “I would paint fear.”

“How would you paint fear?” Ms. Kovaliova asked him.

“Darkness,” Kyryl replied.

Russia carried out its third large-scale bombardment of Ukraine in a week on Monday, with explosions ringing out early in the morning in Kyiv and several other cities after a volley of missiles was fired on the first day of the school year.

The attacks extended Russia’s terrorizing assaults on cities across Ukraine that began a week ago, even as it pushes forward with fierce attacks along the frontline in Ukraine’s East.

Ukraine has responded by launching drones at refineries and electrical plants in Russia, including one near Moscow on Sunday, causing fires and other damage. The Monday attack came around 5:30 a.m., after a countrywide air alert, and after a missile the night before had struck an orphanage in the northeastern city of Sumy, wounding two children and 11 adults, according to the city council and Ukraine’s public broadcaster, Suspilne.

The attack stood out for the number of ballistic missiles fired at Kyiv, said Serhiy Popko, the military administrator in Kyiv, but early reports suggested that casualties and damage were minor.

The Air Force said it had shot down nine ballistic missile but did not specify where, and that in total Russia had fired 58 missiles and one-way attack drones. Ballistic missiles pose a greater risk of breaking through air defenses as they fly much faster than cruise missiles.

The Russian attack prompted Poland, a member of the North Atlantic Treaty Organization, to scramble fighter jets along its southeastern border, but there were no reports of missiles crossing into Polish airspace.

The bombardment came amid a rising tempo in the war on the ground and in the air. Near the threatened eastern Ukrainian city of Pokrovsk, Russian troops attacked 63 times in the past 24 hours, Ukraine’s general staff said. In the air, Ukraine lost a prized Western-supplied F-16 fighter jet — one of only a half-dozen or so they possess — in a crash a week ago, amid the swirl of a major Russian drone and missile attacks.

Just hours after the explosions, children in Ukraine began returning to classes. In cities near the front, nearly all education takes place online, but many schools are open in Kyiv.

“My first fear was that Russians may target the educational institutions because it’s the beginning of the school year,” said Anna Pantyukhova, a mother of two boys, who are 11 and 14. The family waited out the air raid and “when it was over, I quickly got them ready, and they were glad to be going back to school,” she said.

Nikita Deyev, 13 and in the ninth grade, said he spent the early morning in a bomb shelter, then got ready for school. “I had no doubt I would go, even though there were strikes in the morning,” he said.

Schools in Ukraine must provide bomb shelters for students or operate only online, under a law that came into force after Russia invaded the country in 2022.

Last year, only about half of Ukrainian school children had access to in-person education, with the remainder displaced by the war or enrolled at schools without bomb shelters.

Teachers escort children to the shelter, often the basement of a school, during air alerts. If an alert is in effect at the start of the school day, parents are asked to wait until it is over before dropping off their children.

On Monday, the authorities announced an all-clear around 6:30 a.m., allowing schools to open nationwide for the first day of the school year, when children traditionally wear embroidered shirts and bring flowers for their teachers.

Mr. Popko, the military administrator, said that in addition to the ballistic missiles fired at Kyiv, Russia had fired more than 10 cruise missiles.

The cruise missiles, which are slower than ballistic missiles but can change direction during flight, maneuvered for about two hours before setting a course toward Kyiv, arriving simultaneously with the ballistic missiles, he said in a post on social media.

Debris from intercepts by antiaircraft missiles over the city fell in four districts, setting four cars on fire and damaging commercial buildings, Kyiv’s mayor, Vitali Klitschko, said in a statement. Mr. Klitschko wrote that two people had been wounded.

The authorities also reported explosions in Kharkiv, not far from the Russian border in northeast Ukraine, following bombardments there on Friday and Sunday.

The regional prosecutors said Monday that they had recovered wreckage of a type of North Korean missile, a Hwasong-11, from the site of one early morning strike in the city. The office said the identification was preliminary, based on an early examination of debris. The Ukrainian authorities have earlier reported finding debris from North Korean-made missiles in the city.

Before the attack on Monday, President Volodymyr Zelensky of Ukraine said that over the previous week Russia had fired more than 160 missiles of various types, 780 guided aerial bombs and 400 attack drones at Ukrainian targets.

Ukrainian officials have appealed to allies to allow the use of long-range weapons provided by the West, such as rockets and cruise missiles, to strike back at targets in Russia.

Ukraine’s military is stepping up strikes with domestically produced drones. On Sunday, Russia’s military claimed to have thwarted a major Ukrainian drone attack, but fires at refineries and power plants suggested that at least some had gotten through.

Maria Varenikova, Natalia Novosyolova and Anna Lukinova contributed reporting.

For years, she had been losing hair and weight. She had started forgetting whole days, and sometimes appeared to be in dreamlike trances. Her children and friends worried she had Alzheimer’s.

But in late 2020, after she was summoned to a police station in southern France, she learned a far more shattering story.

Her husband of 50 years, Dominique Pelicot, had been crushing sleeping pills into her food and drink to put her into a deep sleep, the police said, and then raping her. He had ushered dozens of men into her home to film them raping her, too, they said, in abuse that lasted nearly a decade.

Using the man’s photographs, videos and online messages, the police spent the next two years identifying and charging those other suspects.

On Monday, 51 men, including Mr. Pelicot, went on trial in Avignon, in a case that has shocked France and cast a spotlight on the use of drugs to commit sexual abuse and the broader culture in which such crimes could occur.

The accused men represent a kaleidoscope of working-class and middle-class French society: truck drivers, soldiers, carpenters and trade workers, a prison guard, a nurse, an I.T. expert working for a bank, a local journalist. They range in age from 26 to 74. Many have children and are in relationships.

Most are charged with raping the woman once. A handful are accused of returning as many as six times to rape her.

The victim, who has divorced her husband and changed her surname since his arrest, is now in her 70s.

Since his arrest, Mr. Pelicot, 71, has “always declared himself guilty,” said Béatrice Zavarro, his lawyer. “He is not at all contesting his role.”

Other defendants have denied the rape charges, with some arguing that they had the husband’s permission and thought that was sufficient, while others claimed they believed the victim had agreed to be drugged.

When the police showed the victim some of the photographs they say her husband had carefully classified and stored, she expressed deep shock. She and her husband had been together since they were 18. She had described him to the police as caring and considerate.

She had no memory of being raped, by him or the other men, only one of whom she recognized, she told the police, as a neighbor in town.

The first time she will consciously witness the rapes, her lawyer Antoine Camus says, will be in the courtroom when the video recordings are played as evidence.

The trial comes at a moment of heightened scrutiny of the handling of sexual crimes in the country. Rape is defined in French law as an “act of sexual penetration” committed “by violence, coercion, threat or surprise.” A number of feminist lawmakers want to amend that wording to say explicitly that sex without consent is rape, that consent can be withdrawn at any time, and that consent cannot exist if sexual assault is committed “by abusing a state impairing the judgment of another.”

“There is a kind of naïveté on the topic of predators in France, a kind of denial,” said Sandrine Josso, a lawmaker who led a parliamentary commission into what is known in France as “chemical submission” — drugging someone with malicious intent. She started the commission after she says she became the victim of a drugging last year. A senator is being investigated on accusations that he slipped Ecstasy into her Champagne.

Ms. Josso hopes that the Avignon trial will draw attention to the use of drugs to prey on women, and also shed light on the wide profile of predators. “They could be your neighbors, without falling into paranoia,” she said.

Mr. Pelicot seemed like a classic man next door. He was a trained electrician, an entrepreneur and an avid cyclist. His middle child and only daughter, Caroline Darian, her pen name, described him as a warm and present father in a book published in 2022 about the case, “And I Stopped Calling You Papa.” She tried to turn her family trauma into action, forming a nonprofit association, “Don’t Put Me to Sleep,” to publicize the dangers of drug-facilitated crimes.

Her father, she wrote, was the one who drove her to school, picked her up late from parties, encouraged her and consoled her. Her mother was the stable breadwinner, working as a manager in a Paris-area company for 20 years.

When she retired, they moved to a house with a big garden and pool in Mazan, a small town northeast of Avignon. The couple regularly hosted their three children and grandchildren for summer vacations peppered with late dinners on the terrace, where the family debated, held dance competitions and played Trivial Pursuit.

“I think of us as happy,” his daughter wrote. “I thought my parents were.”

None of them harbored any suspicions. Then, in 2020, three women reported Mr. Pelicot to the police for trying to use his camera to film up their skirts in a grocery store, and he was arrested.

The police seized his two cellphones, two cameras and his electronic devices, including his laptop, before releasing him on bail.

On the devices, the police say they found 300 photographs and a video of an unconscious woman being sexually assaulted by many people. They said they also found Skype messages in which the man boasted of drugging his wife and invited men to join him in having sex with her while she was unconscious.

Over the course of their investigation, the police found more than 20,000 videos and photographs, many of them dated and labeled, in an electronic folder titled “abuse.” The timeline they built began in 2011. The list of suspects grew to 83.

Two months after his initial arrest, Mr. Pelicot was arrested again and charged with aggravated rape, drugging and a list of sexual abuse charges. He is also accused of violating the privacy of his wife, daughter and two daughters-in-law on suspicion of illegally recording, and at times distributing, intimate photos of them.

If he is found guilty, he faces up to 20 years in prison.

During interviews with the police, the details of which were included in an overview of the case by the investigative judge, Mr. Pelicot said he began drugging his wife so he could do things to her, and dress her in things, that she normally refused. Then he started inviting others to participate. He said he never asked for or accepted money.

He met most of the men, the investigating judge’s report stated, in a chat room on a notorious, unmoderated French website implicated in more than 23,000 police cases in France alone from 2021 to 2024. It was finally shut down, and its owner arrested, in June after an 18-month investigation stretching across Europe.

The chat room where most of the men met Mr. Pelicot was called “a son insu,” which means “without their knowledge.”

Over the years, Mr. Pelicot told the police, he developed rules for the visitors to ensure that his wife did not wake: no smoking or cologne; undress in the kitchen; warm hands under hot water or on a radiator, so their cold touch would not jolt her. At the end of each night, according to the investigating judge’s report, he cleaned his wife’s body.

Of the 83 suspects, the police identified and charged 50.

Only one of the men is not charged with rape, assault or attempted rape of Mr. Pelicot’s wife. Instead, that man is accused of following the same model, and drugging his own wife to rape her. Mr. Pelicot is also charged with raping the man’s wife while she was drugged.

Five of the men also face charges for possessing child sexual abuse imagery.

Mr. Pelicot is also being investigated in the rape and murder of a 23-year-old woman in 1991 and the attempted rape of a 19-year-old in 1999. He admitted to the attempted rape, according to Florence Rault, the lawyer representing the victims in both cases, but denies any involvement in the 1991 homicide.

The story has prompted some soul-searching among doctors, since Mr. Pelicot’s wife had visited gynecologists and neurologists over a series of mystifying symptoms, but had received no diagnosis, according to her daughter.

“What I found disturbing for us doctors was that no doctor considered this hypothesis,” said Dr. Ghada Hatem-Gantzer, a well known obstetrician-gynecologist and expert in violence against women. She and a pharmacist, Leila Chaouachi, have now developed training for doctors and nurses on the symptoms that victims of drug-facilitated assault can experience.

Contrary to popular belief, most cases occur at home, not at bars, said Ms. Chaouachi, who runs annual surveys on such offenses in France. Most victims are women, the surveys show, and around half of the victims do not remember the attack, because of blackouts, she said.

In the case going to court in Avignon, some of the accused admitted guilt to the police. According to the investigating judge’s report, many claimed that they were tricked into having sex with a drugged woman — lured by a husband for a three-way encounter and told she was pretending to sleep, because she was shy.

Several said they believed that she had consented to being drugged and raped as part of a sex fantasy. Some said they did not believe it was rape, because her husband was there and they believed he could consent for both of them.

“It sends shivers down the spine regarding the state of affairs in French society,” said Mr. Camus, who is also representing Ms. Darian and many other members of the family. “If that’s the conception of consent in sexual matters in 2024, then we have a lot, a lot, a lot of work to do.”

President Vladimir V. Putin of Russia arrived in Mongolia late Monday night for his first state visit to a member of the International Criminal Court since it issued a warrant for his arrest in March 2023.

The court accused Mr. Putin and his commissioner for children’s rights of being personally responsible for the “unlawful deportation” and transfer of Ukrainian children to Russia.

In advance of Mr. Putin’s trip, the I.C.C. stated that Mongolia was obligated to arrest Mr. Putin, but Mongolia is heavily dependent on Russia for fuel, and an arrest was considered extremely unlikely.

The Kremlin has shrugged off the possibility.

“There are no worries, we have a great dialogue with our friends from Mongolia,” Dmitri S. Peskov, the Kremlin’s spokesman, told reporters on Friday, noting that “all aspects of the visit have been thoroughly prepared.”

Mr. Putin was greeted by what appeared to be a Mongolian military guard at the airport and was spending the night in the capital, Ulaanbaatar, a sign that he is comfortable being in the country.

Mr. Putin’s visit on Tuesday, at the invitation of Mongolia’s president, Ukhnaa Khurelsukh, and in defiance of the I.C.C. arrest warrant, serves as a reminder that Russia still commands strategic sway over its southern neighbor despite efforts to hedge.

With the visit, “Putin gets a symbolic win for sure,” said Alexander Gabuev, the director of the Carnegie Russia Eurasia Center in Berlin. For Mongolia, he said, the visit shows that the need to maintain the relationship with Moscow outweighs the country’s pledge in 2002 when it signed the Rome Statute ratifying its membership in the I.C.C.

He added that Russia’s adversaries would have to “think twice” about the narrative that “Putin is pariah, he’s ostracized and whenever there is an I.C.C. warrant for a country that’s ratified the Rome Statute, that he will be arrested.”

The international court, based in The Hague in the Netherlands, issued a warrant for Mr. Putin’s arrest last year, accusing him of committing war crimes with the abduction and deportation of Ukrainian children. The court also issued a warrant for Russia’s commissioner for children’s rights, Maria Lvova-Belova.

The I.C.C. has no enforcement mechanism. Countries that have signed on to the court are supposed to detain those who are subject to its arrest warrants. Russia is not a signatory to the court and has consistently rejected its authority.

Mongolia, a landlocked democracy wedged between Russia and China, treads a careful political line in balancing between its two far more powerful neighbors. That has included taking a neutral stance on the war in Ukraine.

While it has looked to the West to ease some of its geopolitical pressure, hosting high-level guests like President Emmanuel Macron of France, Secretary of State Antony J. Blinken, and the British foreign secretary, David Cameron, it is also economically reliant on its far larger neighbors.

Mongolia shares a 2,100-mile border with Russia and relies on the giant gas-producing neighbor for 95 percent of its fuel. It tries to maintain steady ties with Moscow to help balance relations with Beijing, which also holds considerable influence over Ulaanbaatar by purchasing virtually all Mongolia’s commodity-driven exports.

“The Mongolian political establishment thinks it is easier to manage secure and predictable relations with Moscow” by hosting Mr. Putin, said Munkhnaran Bayarlkhagva, an independent geopolitical analyst who used to work at the National Security Council of Mongolia.

“Ulaanbaatar is choosing to have predictable relations with Moscow and do the damage control later,” Mr. Bayarlkhagva said. “After all, geography cannot be changed.”

Mr. Bayarlkhagva said Mongolia likely determined that there would be little blowback for Mr. Putin’s visit given that there is precedent for members of the International Criminal Court defying the Rome Statute. In 2015, South Africa refused to arrest Sudan’s then president, Omar al-Bashir, during his visit to Johannesburg despite the fact that he was wanted by the International Criminal Court for alleged genocide and war crimes in Darfur. Last year, Johannesburg asked the I.C.C. for an exemption from arresting Mr. Putin so he could attend the BRICS summit of Brazil, Russia, India, China and South Africa. When it was not granted, Mr. Putin chose to skip the summit instead.

Still, Mongolia’s decision to invite Mr. Putin was condemned by human rights watchdogs.

“Welcoming Putin, an I.C.C. fugitive, would not only be an affront to the many victims of Russian forces’ crimes, but also undermine the crucial principle that no one, no matter how powerful, is above the law,” Maria Elena Vignoli, international justice senior counsel at Human Rights Watch, said in a statement ahead of the visit.

There are strong connections between the ruling Mongolian People’s Party and Russia, a relationship that dates back more than a century to when the People’s Party helped establish Mongolia’s socialist republic with the backing of the Soviet Red Army. Even after Mongolia’s democratic revolution in 1990, ties between the Mongolian People’s Party and Russia remained as a source of its political legitimacy.

The stated reason for Mr. Putin’s visit — to commemorate the 85th anniversary of the defeat of Japanese forces at the Battle of Khalkhin Gol by the Soviet and Mongolian armies — provides an “ideological boost” for the Mongolian People’s Party, Mr. Bayarlkhagva said.

Mr. Putin sought to underscore his country’s role as a protector of Mongolia in a written interview for the country’s biggest daily newspaper Unuudur, noting, “More than ten thousand soldiers and commanders of the Red Army gave their lives in the battle for the freedom and independence of Mongolia.”

No announcements are expected to be made about the proposed Power of Siberia 2 gas pipeline, which would help redirect Russian gas supplies that had gone to Europe through Mongolia to reach China instead. In August, Mongolia’s parliament voted not to include the pipeline in its budget for the next four years, in what observers said was indication that it had low expectations that it would be built.

A Western diplomat who spoke on the condition of anonymity because of the sensitivity of the matter said the Mongolian government summoned Western envoys to explain their reasoning behind Mr. Putin’s visit. Among them was the need to secure more supplies of fuel and electricity from Russia to prevent a repeat of the shortages the country faced last winter.

The diplomat said Mongolian officials were asked not to give Mr. Putin a platform to propagandize the war in Ukraine.

Khaliun Bayartsogt contributed reporting.