 During the U.N. outbreak from the Pusan Perimeter in mid-September, the Division controlled Hills 268 and 121, along the southern approach of the Waegwan-Taegu road, one of the key positions.In many cases, the North Koreans fought to the last man, but after suffering a two-day assault by the American 1st Cavalry Division and the 5th Regimental Combat Team, including three flights of U.S. Air Force F–51 Mustang fighters dropping napalm, firing rockets, and strafing runs, they lost the hill.With the loss of these key positions, the 3rd Division's defenses around Waegwan broke apart and its troops began a panic-stricken retreat across Naktong.