NEW : Truck loaded with more than a half-ton of explosives , official says . U.S. military says two Americans assigned to embassy among dead . Pakistani president says of perpetrators : `` These people are not Muslims '' Police `` There was heavy security in the city . '' : They were from Pakistan and Afghanistan.
NEW : Truck loaded with more than a half-ton of explosives , official says . U.S. military says two Americans assigned to embassy among dead . Pakistani president says of perpetrators : `` These people are not Muslims '' Police : They were from Pakistan and Afghanistan.