The document advises captors they can have sex immediately with virgins, and even pre-pubescent girls if "fit for intercourse," reads the institute's translation. Fighters can have sex with non-virgins, although the "uterus must be purified."

Beating the women is allowed but only for disciplinary reasons, the pamphlet, titled "Questions and Answers on Taking Captives and Slaves," says. The buying, selling and gifting of slaves are also permitted "for they are merely property."

“The content, while it is abhorrent and shocking, is not surprising – we know that IS ideologues have justified and legitimated slavery in past publications," Charlie Winter of the anti-extremism think tank Quilliam told the Independent.

After the guide was posted online sometime in October or November, armed men in Mosul, Iraq, now controlled by the Islamic State, passed out print versions on Friday, CNN reported. "Most are shocked, but (we) cannot do much about it," an unidentified resident told the news network.

The Washington Post notes that the Islamic State's treatment of women is already well-documented. Militants have kidnapped thousands, and testimony by women from the Yazidi sect, who were taken into custody by ISIS, have reinforced accounts of the sexual brutality.