By this time , the US 2nd Infantry Division suffered 1 @,@ 120 killed , 2 @,@ 563 wounded , 67 captured and 69 missing during its time at Pusan Perimeter . This included about 180 casualties it suffered during the First Battle of Naktong Bulge the previous month . American forces were continually repulsed but able to prevent the North Koreans from breaking the Pusan Perimeter . The division had numbered 17 @,@ 498 on September 1 , but was in excellent position to attack despite its casualties . The 1st Provisional Marine Brigade suffered 185 killed and around 500 wounded during the Battle of Pusan Perimeter , most of which probably occurred at Yongsan .