US looking into whether hostage was kept by IS leader

US intelligence agencies are investigating the possibility that the Islamic State militant leader killed Friday was the captor of American hostage Kayla Mueller for a time.
Adam Schiff, the top Democrat on the House intelligence committee, confirmed the line of inquiry at a breakfast with reporters today, but declined further comment.
ABC News first reported that US officials believe Mueller, whose death was announced in February, spent time in the custody of the Tunisian Islamic State finance man known as Abu Sayyaf.
A US official today said Sayyaf's real name was Fathi ben Awn ben Jildi Murad al-Tunisi.
Murad was killed Friday during a rare ground operation in Islamic State-held territory in Syria by Delta Force operators.

His wife, known as Umm Sayyaf, was taken into custody and is being interrogated, US officials say. She is cooperative and providing "a trove" of intelligence, said a Congressional official briefed on the matter.

Intelligence analysts are also sifting through reams of electronic data seized at the site, the official said.
Murad had a number of aliases, the US official said, but officials believe that Murad is his real name. Murad is believed to be the Islamic State's head of oil operations.
Both officials spoke on condition of anonymity because they were not authorized to discuss the matter publicly.
The Islamic State group said Mueller was killed in a Jordanian air strike, but U.S. Officials have cast doubt on that assertion.

Mueller and her Syrian boyfriend were taken hostage in August 2013 after leaving a Doctors Without Borders hospital in Aleppo, Syria. The boyfriend was later released. White House spokeswoman Bernadette Meehan declined to address the issue.
"We are currently debriefing the detainee to obtain intelligence about ISIL operations," she said. "We are also working to determine any information she may have regarding hostages - including American citizens who were held by ISIL.