The United States carried out a pre-planned air strike in northern Syria on Wednesday to destroy an ammunition cache and military equipment that were left behind as U.S. personnel prepare for a withdrawal from northeast Syria, U.S. officials said.

Colonel Myles Caggins, an Iraq-based spokesman for the U.S.-led coalition battling Islamic State, said the strike involved two F-15e fighter jets from the U.S.-led coalition, which fired on the Lafarge Cement Factory after all coalition forces had left the facility.