NEW : Grandmother talks of loss of SEAL . The military is looking into whether the helicopter was vulnerable to being shot down . Helicopter was on a reinforcement mission , U.S. military official says . 22 of the dead are U.S. Navy SEALs , U.S. officials say . The helicopter crashed in Afghanistan's Helmand province Saturday after being hit by an RPG.
NEW : Grandmother talks of loss of SEAL . Helicopter was on a reinforcement mission , U.S. military official says . 22 of the dead are U.S. Navy SEALs , U.S. officials say . The helicopter crashed in Afghanistan's Helmand province Saturday after being hit by an RPG.