U.S. airstrikes targeting Islamic State surge 300 percent

The majority of the airstrikes were carried out in support of Operation Roundup, the ground campaign led by the Syrian Democratic Forces or SDF — the American-backed coalition of Kurdish and Arab paramilitaries — to eliminate remaining pockets of ISIS resistance in the Euphrates River Valley.

“We want to leave behind security elements that are going to be able to maintain [security] at the local level,” the three-star general said. “That’s sort of a long-term aim we have, as we push down the Euphrates River Valley, and that progress is continuing.”