HRW recounted the story of Hanan, 26 , whose husband had already fled Hawijah, who was captured by ISIS along with other women when they also attempted to escape the town.
ISIS terrorists told her that her husband's flight made her an apostate and that she should marry the local terror leader.
When she refused, she was blindfolded, beaten with plastic cables, suspended by her arms for some time and then raped.
"The same guy raped me every day for the next month without a blindfold, always in front of my children," Hanan told Human Rights Watch.
"Little is known about sexual abuse against Sunni Arab women living under ISIS rule," said Lama Fakih, deputy Middle East director at HRW.
"We hope that the international community and local authorities will do all they can to give this group of victims the support they need," she said.
ISIS terrorists believe the mass rape and sexual enslavement of women from the Yazidi minority - who are neither Arab nor Muslim - are legitimate as they are "polytheists". The accounts collected by Human Rights Watch often refer to ISIS accusing the women of apostasy, or abandoning their faith, before abusing them.
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