on condition of anonymity because he was not authorized to speak to the media about security matters.

He said IS lost most of the income it once made from oil and taxes imposed in areas it controlled. The group now relies on selling gold and other reserves that they had accumulated after declaring their caliphate in June 2014. He said the money is being used to buy weapons and finance attacks in Iraq and Syria.

Another Iraqi intelligence official said IS has begun restructuring its command, relying more on non-Iraqi commanders after most of its leaders were killed in coalition strikes.

The Islamic State group once held an area the size of Britain across vast territories straddling parts of Iraq and Syria, running a so-called caliphate and planning international attacks fromits headquarters in the Syrian city of Raqqa. Tens of thousands were killed in both countries as an array of local forces, some backed by a U.S.-led coalition, eventually drove the extremists out of virtually all the lands they once held.

Iraq's then-Prime Minister Haider al-Abadi declared final victory over the group on Dec. 9, 2017. Two months earlier, the coalition, working with Kurdish-dominated fighters known as the Syrian Democratic Forces, liberated Raqqa after a bombing campaign that decimated much of the city.

The area that IS still holds in Syria represents less than 1 percent of the territory it controlled at its height. The pocket is home to some 15,000 people, including IS fighters and their families. The U.S. military estimates there are about 2,000 remaining IS fighters there.

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