“Abu Sayyaf was a senior ISIL leader who, among other things, had a senior role in overseeing ISIL’s illicit oil and gas operations — a key source of revenue that enables the terrorist organization to carry out their brutal tactics and oppress thousands of innocent civilians,” she said in a statement.

“He was also involved with the group’s military operations.”

Abu Sayyaf was a Tunisian citizen, a senior administration official said.

A U.S. official with direct knowledge of the intelligence and the ground operation described Sayyaf as “CFO of all of ISIS with expertise in oil and gas” who had an increasing role in operations, planning and communications.

“We now have reams of data on how ISIS operates, communicates and earns its money,” the official told CNN, referring to some of the communications elements, such as computers, seized in the raid.

Umm Sayyaf, his wife, is currently in military detention in Iraq. A young woman from the Yazidi religious minority was rescued.

“We suspect that Umm Sayyaf is a member of ISIL, played an important role in ISIL’s terrorist activities, and may have been complicit in the enslavement of the young woman rescued last night,” said Meehan. ISIL is an alternative acronym for ISIS.

Airdrop, firefight

There is reason to believe that Abu Sayyaf may have been in contact with ISIS leader Abu Bakr al-Baghdadi, sources familiar with the operation told CNN.

Although he was not taken alive, U.S. forces did capture some of his communications equipment, the sources said.

More details are starting to emerge of how the overnight raid deep in ISIS-controlled territory was carried out.

There was hand-to-hand combat during the operation, which was helicopter-borne, the sources told CNN.