December 16, 1950 – The remaining forces of X Corps in the inland town of Hamhung withdraw to Hungnam. About 12 Chinese and North Korean divisions attack Hungnam, but are held off with the help of heavy naval shelling and carrier-based aircraft. Retreating from the north faster than they had counter-invaded, the Eighth Army crossed the 38th parallel border in mid December. The UN morale hit rock bottom when commanding General Walton Walker of the US Eighth Army was killed on 23 December 1950 in an automobile accident. In the northeast Korea by 11 December, the US X Corps managed to cripple the PVA 9th Army Group while establishing a defensive perimeter at the port city of Hungnam. The X Corps were forced to evacuate by 24 December in order to reinforce the badly depleted US Eighth Army to the south.