As fighting raged between Islamist extremists and armed residents of the northern Iraqi town of Qahtaniya, Abdal Ali Aliyas had a split-second decision to make.
There were two roads leading to the countryside. Aliyas fled by the gravel road. His 18-year-old sister, Amsha, took the paved road.
The choice turned out to mean the difference between life and death, freedom and captivity.
Whereas Aliyas, his wife and several relatives escaped to safety, Amsha, her husband and others were snared along the main road by the marauding extremists of Islamic State. They shot and killed her husband and several other fleeing men, and took Amsha, who was five months pregnant, hostage.
In their march across northern Iraq this month, Islamic State fighters have abducted hundreds of Yazidis, followers of an ancient religion whom the Sunni Arab militants view as apostates. The captives are men and women, teenagers and toddlers, expectant mothers and frail grandparents being held in spartan conditions in jails, apartments, mosques and airplane hangars in militant-run towns across the north.
Iraqi officials do not have an accurate count of the number of people being held. But Amnesty International, which has tracked the abductions, believes they number at least several hundred, perhaps as many as 2,000.
For displaced Yazidis now living in the relative safety of government-controlled towns, the plight of the missing is a source of endless torment. Aliyas, a 23-year-old teaching student, shook his head repeatedly as he considered the simple choice that ripped his family apart.
"People said the main road was safer, but I took a chance," he said. "Amsha was unlucky."
Many captives, especially armed Yazidi men who clashed with the extremists as they advanced through the northern region of Sinjar on Aug. 3, are believed to have been executed, human rights activists and relief workers say. Other men have reportedly been herded into mosques and ordered to convert to Islam, while women are forced to wear veils in keeping with the extremists' strict interpretation of the Muslim faith.
The prisoners have told their stories to relatives using cellphones they kept with them as they were rounded up, shedding a bit of light on the militants' ideology and movements. But the accounts given by family members are incomplete and sometimes conflicting, and activists say that some of the most chilling reports circulating among the displaced, such as mass rapes or forced marriages of young women, have not been proved.
What is unmistakable is the desperation among Yazidi families, for whom the few fleeting phone conversations confirm that their loved ones have survived a few more nights in captivity but offer scant hope that they will soon be reunited.
Until his sister called one evening last week, Aliyas said, "we didn't hear from her for six days. I thought she was dead. What else can you think?"
He and other relatives were crammed with nine other families into a four-room apartment in Sharya, 35 miles north of the militant-held city of Mosul. Relief workers say that more than 25,000 Yazidis have sought refuge in Sharya, including many who arrived after U.S. airstrikes against Islamic State near Mt. Sinjar helped create a path to safety.
In their most recent conversation, Amsha said she was being kept with several other women in an apartment in Mosul. She said the militants were feeding them but preventing them from venturing outside. She was growing increasingly worried about the health of her unborn child, Aliyas said.
Just as troubling, she reported that a few nights earlier the militants had taken several unmarried female captives away from the group, including her husband's 17-year-old sister. She didn't know where they were and was afraid to ask the two militants — one Iraqi, the other possibly Afghan or Tunisian — assigned to guard her.
"We are done for," she told Aliyas, adding, "Just tell me that you and the family are OK."
The Yazidis' heterodox faith, which includes elements of Zoroastrianism, Christianity and Islam, has long made them a target of Islamic fundamentalists in Iraq, where most of the sect's 700,000 worldwide adherents reside. In 2007, four truck bombs exploded in Qahtaniya and surrounding Yazidi towns, killing more than 500 people in one of the deadliest coordinated attacks of the Iraqi civil war.
The bombings, for which U.S. officials blamed Sunni extremists, killed Aliyas' sister-in-law and her three children. Seven years later, Aliyas' 65-year-old mother can barely speak about the family's latest loss.
"This is our destiny," Aliyas said.
Khider Domla, a relief coordinator in Sharya, has compiled page after page of such cases, including extended families in which more than 20 people are missing.
Several Yazidi women have told him that they had been bundled into vehicles in the middle of the night and moved to another town, only to be moved again after one or two nights. Domla believes the militants are using the captives as human shields and may even be turning a blind eye to the prisoners' phone calls to sow confusion about their whereabouts.
"This way the message spreads that there are civilian prisoners in certain towns," Domla said. "That makes the United States think: OK, maybe we shouldn't do airstrikes there."
It isn't clear whether the captives have influenced American bombing plans.
Fewer male prisoners have called relatives, perhaps because the women were not searched as thoroughly by the conservative militants and were better able to hide their phones.
Khider Ismael Khalaf, a mechanic, had no word from his 23-year-old son, Raed, and assumed he had been killed until Islamic State supporters began circulating an Internet video last week showing what they described as dozens of Yazidi "converts" to Islam. There in the crowd, in an unidentified mosque with black Islamic State banners hanging from the walls, was Khalaf's son, wearing a black shirt with his arms folded.
Donatella Rovera, a senior Amnesty International investigator in Iraq, said Yazidi men who pretended to become Muslims reportedly were given better treatment, such as being allowed to move into houses with their families.
"It's quite clear that those who converted did not do so of their own free will," Rovera said. "So it's not clear what the [militants'] intention is for … these people in the long term."
Conditions appear to be more dire for captives in the northern city of Tall Afar, where hundreds of people are believed to be held at an airport. A farmer from the Sinjar area, Aliyas Khider Abdalla, said 13 members of his extended family, including his wife and three children, were being held there and given just two pieces of bread daily to share among all of them.
Four women had died while giving birth, and dozens of children were ill because of hunger, he said. The accounts could not be confirmed.
The militants reportedly burned the Yazidis' identity cards and told them they would be issued new documents as "subjects of the Islamic State."
"They are very scared, and they would rather be dead than be in this situation," Abdalla said. "My wife is saying, 'Just ask the United States to strike now and kill them, no matter what happens to us.'"
Many in Sharya are racked with survivors' guilt. One 26-year-old Yazidi woman from Sinjar called her father two weeks ago from Tall Afar. Sobbing, she said that militants had called her a devil worshiper and raped her repeatedly.
Domla, who was in touch with the woman, said she called back a few days later to say she was contemplating suicide. "She wanted to tell him sorry, in case he didn't see her again," he said.
One afternoon last week, Domla went to check on the man. But his brother said he had left that morning to return to Sinjar, to try to find his daughter.