The most senior female Islamic State captive has played a central role in the hunt for Abu Bakr al-Baghdadi, helping identify safe houses used by the fugitive terrorist leader and in one case pinpointing his location in Mosul, the Guardian can reveal.

The Isis woman, Nisrine Assad Ibrahim, better known by her nom de guerre, Umm Sayyaf, has helped the CIA and Kurdish intelligence officers build a detailed portrait of Baghdadi’s movements, hideouts and networks, investigators have disclosed. The claims have been confirmed by Umm Sayyaf in her first interview since being captured in a Delta Force raid in Syria four years ago that killed her husband, the then Isis oil minister.

Umm Sayyaf, 29, is a highly controversial figure who has been accused of involvement in some of the terror group’s most heinous crimes, including the enslavement of the captured US aid worker Kayla Mueller and several Yazidi women and girls, who were raped by senior Isis leaders.

Read more HERE