U.S.-led air strikes on Islamic State (IS) cash-storage sites have cost the militant group hundreds of millions of dollars, a U.S. military spokesman says.
The United States is trying to cut IS revenue through air strikes targeting its oil-production and cash-storage facilities.
U.S. officials believe the extremist Sunni group has grown more dependent on cash as its access to the banking system has been cut through sanctions.
Colonel Steve Warren, spokesman for the U.S.-led coalition fighting IS, said the strikes on cash storage sites had destroyed "hundreds of millions of dollars" worth of currency. He declined to be more specific.
Warren previously estimated that strikes against IS targets had eliminated "tens of millions of dollars."
As of mid-January, the coalition had struck 10 IS cash-storage sites in Iraq and Syria, he said.
As proof that the strikes are taking a toll, Warren noted reports that IS has had to reduce fighters' salaries by as much as 50 percent.