U.S. forces have recovered the bodies of 16 American troops killed in a crash of a U.S. helicopter in eastern Afghanistan and other U.S. troops who had been at the scene were unaccounted for, the Pentagon said on Thursday. U.S. military officials have said the MH-47 Chinook was probably struck by a rocket-propelled grenade during an anti-al Qaeda operation before it crashed on Tuesday in the mountainous Kunar province bordering Pakistan, Reuters said. The casualties were the heaviest suffered by U.S. forces in a combat incident in Afghanistan since they invaded and overthrew the Taliban in 2001. Earlier the BBC quoted U.S. military officials as saying 13 bodies had been recovered from the crash site but seven servicemen, including some who had been figting on the ground, were unaccounted for. The report said some may have been captured. "At this point, we have recovered all 16 bodies of those servicemen who were on board the MH-47 helicopter," Marine Corps Lt. Gen. James Conway, director of operations for the U.S. military's Joint Staff, told a Pentagon briefing. --More 2252 Local Time 1952 GMT