Early one morning in November 2015, Nouhad put on a solid black niqab — only her eyes showing — and snuck out of the house in Mosul were she had been held captive for more than a year.

“The ISIS man that held me went to Syria for two days,” Nouhad says. “I knew it was my chance to escape.”

She was lucky. A neighbor, who was not with ISIS, had given her a phone. She called her father and told him where she was — the neighborhood and the name of the pharmacy on the corner. He raised the $7,000 needed to pay a smuggler to rescue her.

“I was so happy to come home,” Nouhad says, “but sad to find most of my family wasn’t here. My brothers and sisters are missing.”

When ISIS stormed Mount Sinjar in August 2014, they kidnapped and killed thousands of Yazidis, a minority religious sect that the terror group accuses of worshipping the devil. Nouhad was just 16 years old when she was abducted. Like hundreds of other women and girls, she was eventually brought to Mosul, the largest city under ISIS control, where she was raped, beaten and sold. She says she was abused not just by the man who owned her, but his entire family.

Still, the decision to leave wasn’t easy. She tears up as she talks about having to abandon her 4-month-old son. His father was the ISIS commander who owned her.

“I cannot forget him,” she says, “even if his father is ISIS. He is from me.”

Since her escape, Nouhad has been going to the Women and Girls Support Center in Dohuk. The center has helped more than 800 women and girls over the past two years who have escaped from ISIS captivity. Some arrive sick, with sexually transmitted infections, tuberculosis or scabies. Others arrive pregnant, carrying the child of their captor. At the center they get medical assistance and psychosocial support, key for these women and girls trying to reintegrate into society.

“Each one of them has a different story of how they survived,” says Khidher Domle, who helps women reach the center once they’ve escaped.

Domle says almost 4,000 Yazidis remain in ISIS captivity, and he estimates that at least 700 women are still held inside Mosul.

“We are expecting more sexual violence survivors to show up once the Mosul operation is completed,” says Ramanathan Balakrishnan of the UN Population Fund. Balakrishnan says they are now expanding the center to accommodate the new wave of victims expected to arrive as Iraqi forces liberate areas under ISIS control.

Nouhad’s sister and several of her friends are among those still held inside Mosul.

“We are all waiting for the day they liberate Mosul,” says Nouhad. “And all our girls will be free.”

But Domle is less optimistic. Most Yazidi women have been sold or given to ISIS commanders or senior fighters. In previous battles, these men have often been the first to flee, taking the women with them. There have already been reports that senior ISIS members have left Mosul.

“Before liberating Shaddadi [in Syria], we knew there [were] more than 150 women there, but when they liberated it, they didn’t find anyone. When we liberate[d] Falluja, the same. We knew there are more than 100 women there, but [only found] two women,” Domle says. “We worry the same thing will happen in Mosul.”