Nearly 12 insurgents , 20 U.S. contractor killed in attack on Bagram Air Base . Virginia McCabe , could not say if flights into and out of the air base had been stopped and said that authorities are investigating how the incident started . The Todd Breasseale said Nearly 12 armed men in suicide vests stormed the base . U.S. official says insurgents did n't breach U.S. . Militants have lobbed rockets into base in previous attacks .
Nearly 12 insurgents , 20 U.S. contractor killed in attack on Bagram Air Base . The Todd Breasseale said Nearly 12 armed men in suicide vests stormed the base . U.S. official says insurgents did n't breach U.S. . Militants have lobbed rockets into base in previous attacks .