NEW : Grandmother died of loss of blood . Helicopter was on a reinforcement mission , a military official says . `` All of those killed in this operation were true heroes who had already given so much in the defense of freedom . 22 of the dead are former Navy SEALs , U.S. officials say . A few belonged to the same unit that killed Osama bin Ali .
NEW : Grandmother died of loss of blood . Helicopter was on a reinforcement mission , a military official says . 22 of the dead are former Navy SEALs , U.S. officials say . A few belonged to the same unit that killed Osama bin Ali .