WASHINGTON (AP) — The wife of a senior Islamic State leader who was killed in a U.S. raid last year has been charged in federal court with holding American Kayla Mueller hostage and with contributing to the aid worker's death, the Justice Department says. Nisreen Assad Ibrahim Bahar, also known as Umm Sayyaf, admitted after her capture last May that she and her husband kept Mueller captive along with several other young female hostages, according to an FBI affidavit filed in the case. The criminal complaint, filed by federal prosecutors in Alexandria, Virginia, charges Umm Sayyaf with conspiracy to provide material support to a foreign terror organization, resulting in death. Mueller was transferred in September 2014 along with two Kurdish women of Yazidi descent from an Islamic State prison to the Sayyafs, according to the FBI affidavit, which says the couple at times handcuffed the captives, kept them in locked rooms, dictated orders about their activities and movements and showed them violent Islamic State propaganda videos.