key to the advance of the 25th Division lay in its center where the KPA held the heights and kept the 24th Infantry Regiment under daily attack. The 27th Infantry on the left and the 35th Infantry on the right, astride the roads between Chinju and Masan held their positions and could not advance until the situation in front of the 24th Infantry improved. On September 19 the UN discovered the KPA had abandoned Battle Mountain during the night, and the 1st Battalion, 24th Infantry, moved up and occupied it. On the right, the 35th Infantry began moving forward. There was only light resistance until it reached the high ground in front of Chungam-ni where hidden KPA soldiers in spider holes shot at 1st Battalion soldiers from the rear. The next day the 1st Battalion captured Chungam-ni, and the 2nd Battalion captured the long ridge line running northwest from it to the Nam River. Meanwhile, the KPA still held strongly against the division left where the 27th Infantry had heavy fighting in trying to move forward. The KPA withdrew from the Masan area the night of September 18–19. The KPA 7th Division withdrew from south of the Nam River while the 6th Division sideslipped elements to cover the entire front. Covered by the 6th Division, the 7th had crossed to the north side of the Nam River by the morning of September 19. Then the KPA 6th Division withdrew from its positions on Sobuk-san. The US units rapidly pursued them north, passing over the Battle Mountain positions, which were no longer of strategic importance. Aftermath The US 5th Regimental Combat Team suffered 269 killed, 573 wounded and 4 missing during its battles at the Pusan Perimeter, most of these at Masan. The rest of the 25th Infantry Division suffered 650 killed, 1,866 wounded, four captured and 10 missing during the fight. Another 138 were killed, 646 wounded, and two captured during the division's breakout attack from the Masan battleground. The KPA suffered heavily in the fight, and most became casualties in the attack. By mid-September, the KPA 7th Division was reduced to just 4,000 men, a loss of 6,000 from when it was committed to the perimeter. Only 2,000 men from the KPA 6th Division returned to North Korea, a loss of 80 percent of its strength. Large groups of troops from the divisions were captured as they attempted to