UN troops, particularly South Korean, were also accused of killing or attempting to kill captured KPA soldiers. South Korean civilians, some of whom were leftist or communist sympathizers, were known to have been systematically imprisoned or killed in the Bodo League massacres, some of which have taken place during the battle.Shortly before the Pusan Perimeter fighting, retreating 1st Cavalry Division troops and U.S. warplanes killed an estimated 250-300 South Korean civilians, mostly women and children, in the No Gun Ri massacre. U.S. commanders had adopted a policy of firing on approaching refugee groups, for fear of North Korean infiltrators. Such killings continued during the Naktong River fighting, when commanders declared refugees "fair game" and issued such orders as "shoot all refugees coming across river."