Six U.S. airmen were among 13 people killed early Friday when an American C-130 transport plane crashed while taking off in Afghanistan, a U.S. military official said. The incident occurred shortly after midnight local time (3:19 p.m. ET) at Jalalabad airfield. Six of the dead were U.S. crew members aboard the aircraft. The other victims were five civilian contractors, who were passengers, and two Afghan civilians who were killed on the ground.