WASHINGTON (AP) — The U.S. military has begun to investigate a Taliban attack on a U.S.-British base in Afghanistan last September that killed two Marines and destroyed six aircraft and put on hold the announced promotion of the two-star Marine general who was in charge there at the time, officials said Thursday.

Marine Maj. Gen. Charles M. Gurganus was the senior commander in southwestern Afghanistan when 15 Taliban fighters breached the security perimeter of Camp Bastion in Helmand province and carried out their stunning attack. All but one of the fighters was killed in a Marine counterattack.