Iraqi children, displaced by the siege of Mount Sinjar by Islamic State militants, speak of the lives they left behind. (Reuters)

Iraqi children, displaced by the siege of Mount Sinjar by Islamic State militants, speak of the lives they left behind. (Reuters)

Hundreds of Yazidi women who were captured by Islamic extremists during their sweep through the town of Sinjar are being incarcerated at scattered locations across northern Iraq in what increasingly looks like a deliberate attempt to co-opt them into service as the wives of fighters.

As the militants with the al-Qaeda-inspired Islamic State surged into the area from surrounding Arab villages two weeks ago, snaring those who had not managed to flee, they showed a marked interest in detaining women, notably the youngest and prettiest, according to witnesses, relatives and in some instances the women themselves.

Women were separated from men, then younger women were separated from older ones and most were shunted off in buses or trucks.

Once in custody, the women are presented with a bleak choice.

Those who convert to Islam can be promised a good life, with a house of their own and — implicitly — a Muslim husband, because the extreme interpretation of Islam promoted by the Islamic State does not permit women to live alone.

1 of 10 Full Screen Autoplay Close Skip Ad × Majority of Yazidis return to Iraq View Photos Many who had been trapped at risk of death fled to Syria and now are in northern Iraq, shaken but no longer in imminent danger. Caption Many who had been trapped at risk of death fled to Syria and now are in northern Iraq, shaken but no longer in imminent danger. A Yazidi girl enters the temple in Lalish, Iraq, the Yazidi holy sanctuary. Tens of thousands of the Iraqi minority sect have been displaced after being attacked by the Islamic State militant group. They are spilling across northern Iraq — sleeping in fields, cars and abandoned buildings — but at least they are safe. Sebastian Meyer/For the Washington Post Buy Photo Wait 1 second to continue.

Otherwise, they have been told, they can expect a life of indefinite imprisonment — or, they fear, death.

The accounts of the women’s capture and detention have been assembled from multiple interviews with Yazidi refugees, witnesses, activists and women who have been able to reach out to the outside world using cellphones they were carrying when they were detained. The identities of the women, and some of the specifics of their accounts and communications, are being withheld to protect them from being discovered by their captors.

The accounts point to a chillingly deliberate effort to harness the women into the service of the Islamic State’s project to create a caliphate across the Muslim world, by persuading them to convert and then marrying them to the men of the group.

The women “are considered apostate, and it is haram [forbidden] for Muslims to marry a non-Muslim,” said Hoshyar Zebari, a senior Kurdish leader who until recently served as Iraq’s foreign minister. He puts the number of women detained at more than 1,000.

“Many fighters came from foreign places without wives, so they want the women to convert so that they can become brides of the jihadis,” he said.

Exactly how many women have been caught up in the dragnet is unclear. The Iraqi government claims that 1,500 women have been detained and 500 men executed in the brutal blitz by the extremists through the Sinjar area, where a majority of the residents are Yazidis but some are Christian, Shiite or Sunni Arab.

Women from other sects also have been detained, but the majority of the captives appear to be Yazidis, whose beliefs are considered heretical by the Islamist extremists.

1 of 42 Full Screen Autoplay Close Aug. 10, 2014 Aug. 9, 2014 Saturday Aug. 7, 2014 Thursday Aug. 5, 2014 Tuesday Aug. 4, 2014 Monday Aug. 3, 2014 Sunday Skip Ad × Yazidis cross into Iraqi Kurdistan from Syria View Photos After being stranded on the parched Mount Sinjar for almost a week and then walking 12 miles to seek refuge in Syria, some of the persecuted civilians were able to safely return to the Kurdish region of Iraq with the help of Syrian Kurdish forces. Caption After being stranded on the parched Mount Sinjar for almost a week and then walking 12 miles to seek refuge in Syria, some of the persecuted civilians were able to safely return to the Kurdish region of Iraq with the help of Syrian Kurdish forces. Aug. 12, 2014 Displaced Iraqis from the Yazidi community gather for food at the Nowruz camp in Derike, Syria. Khalid Mohammed/AP Buy Photo Wait 1 second to continue.

The Sinjar Crisis Group, formed by Yazidi activists in Washington, has compiled a list of 1,074 names of female captives reported by their relatives to be in the custody of the Islamic State.

On Saturday, 100 or so women joined the list, turning up crammed into two buses at a school in the town of Tal Afar, where hundreds of the women are already being held, according to an eyewitness. The new arrivals had been detained the previous day in the small village of Kocho, where Kurdish officials and Yazidis say that more than 80 men were lined up and shot before the younger women were separated from the older ones and taken away.

The oldest of the women in Kocho were not detained but are being held there by Islamic State fighters who also spared the oldest men, said Ziad Sinjari, a Kurdish pesh merga commander in Sinjar, citing the account of one of six survivors of the massacre who escaped injured to a nearby village.

Once at the school, the eyewitness said, the youngest women again were parted from older ones and driven away, along with a dozen or so boys between ages 10 and 12 who had apparently been detained with their mothers.

The reports from the massacre at Kocho and its aftermath illustrate a disturbing pattern that has emerged in the two weeks since the majority-Yazidi town of Sinjar was overrun, prompting tens of thousands of panicked adherents of the minority sect to run for their lives to the mountains.

U.S. airstrikes and an airlift of humanitarian supplies helped most of those who fled reach safety in northern Iraq last week, aided also by Kurdish Syrian fighters who battled the extremists to open a corridor for the fleeing Yazidis.

Some did not get away in time.

Among them was an aunt of Haji Kirani, 45, who managed to escape to Dahuk, the city in Iraq’s Kurdistan region where many of the refugees have found sanctuary. His aunt lived in the town of Sinjar and was snatched along with her daughter as the militants surged in — unopposed, the Yazidis say, because the Kurdish pesh merga forces responsible for defending the town fled.

As Kirani ascended the mountain, escaping with the other Yazidis, he received a phone call from his aunt, telling him she was being transported in a truck with scores of other women. Over the next few days, she called several more times, relaying her location as she was moved around — first in a prison, then a hotel in Mosul, and then some kind of “hall” in a location she did not know.

“I can see a lot of trees,” she told him, Kirani recalled.

Then, late last week, the phone calls stopped.

The more lurid rumors of mass rapes and sexual enslavement of the women who were caught appear to be exaggerated. The women who have managed to place phone calls say they have been well, if frugally, treated. Lunch in one of the locations consists of a fistful of boiled rice and dinner of a piece of bread and an egg.

But the Islamic State fighters guarding the women appear to have mostly demonstrated prurient adherence to the tenets of Islam that forbid contact with non-Muslim women. When a local Iraqi guard attempted to fondle a woman in one location where hundreds are being held, a senior guard from Morocco or Algeria — the woman who conveyed the story to a relative was unsure — ordered the molester’s finger to be cut off.

For the most part, the Islamic State men entreat rather than threaten the women to convert, the women say. “They beg us,” one of the women said. “They promise us everything. They say they will give us houses and we will lead happy lives.”

The accounts, however, point, to a hardly less disturbing scenario, of attempts to coerce and intimidate the prisoners into converting or lose their freedom forever. The captives describe incidents replete with sexual innuendo and implicit threats that keep them constantly on edge.

An 11-year-old girl was taken into the yard of the school last week and men gathered to look at her, the witness said. They did not touch her, but women watching from the windows of the classroom were unnerved.

Men show up at and circulate among the women crammed into classrooms, eyeing them and making demeaning comments, she said. “If you were a Muslim I would choose you,” one said, pointing at a woman, the same witness recalled.

In the wake of the initial onslaught against Sinjar, all of the women were taken to Badoosh prison on the outskirts of the city of Mosul, according to multiple reports. Since then, groups of the women have been moved around, leading to fears that they have been killed or sold. Some of those women, however, have simply shown up at other locations a few days later, contacting their relatives to say they are well — suggesting the fighters are seeking both to disperse the women and organize them into groups.

But the fate of some of the women remains unknown. Instead of running up the mountain like many other Yazidis, Nouray Hassan Ali, 40, had taken shelter in the home of a nearby relative with around 40 other members of her extended family when the Islamic State fighters began their onslaught, shortly after 2 a.m. Aug. 3.

After Kurdish pesh merga and local Yazidi fighters ran out of ammunition and began to flee, around 10 Islamic State fighters burst into the house. The men ordered the family outside, lined them up and then divided them into groups according to age and gender, Ali said in an interview in the northern town of Dahuk, where she has now taken refuge.

Most of the fighters were Iraqis, but one appeared to be Pakistani, she said. One was a Kurd, and he spoke to the frightened family members in Kurdish. “He told us they didn’t want to harm us, that we should not be afraid,” she recalled.

Ali, her six children and the other mothers were taken indoors and put into a room. One of the children began to cry that he was thirsty. Their guard dispatched another fighter to fetch a bucket of water. When the fighter returned with the water, he glimpsed at Ali’s 15-year-old daughter and beckoned her to leave the room.

Then, the women heard gunshots, followed by silence. They stepped outside. The bodies of eight men, including Ali’s husband, lay sprawled around the house. The young women, including her daughter, had gone. She has not heard word of her since.