As a result , the ROKA and US troops retreated Escaping to a small area behind a defensive Defending line known as the Pusan Perimeter .

It was a part of the Battle of Pusan Perimeter , and was one of several large engagements fought simultaneously .

The urgency of the threat to Pusan Perimeter prompted Causation the US Marine Corps 1st Provisional Marine Brigade to be brought in to reinforce the US Army troops .

The KPA were outflanked by the Inchon landings on 15 September and on 16 September the UN forces began Process_start their breakout from the Pusan Perimeter which drove the KPA from the area .

It was a part of the Battle Hostile_encounter of Pusan Perimeter , and was one of several large engagements Hostile_encounter fought Hostile_encounter simultaneously .

Forces of the South Korean Republic of Korea Army ( ROK ) , supported Supporting by the United States Navy and United States Air Force ( USAF ) , defended Defending the eastern coast of the country as a part of the Pusan Perimeter .

This battle Hostile_encounter and several others were smaller engagements Hostile_encounter of the Battle Hostile_encounter of Pusan Perimeter .

They continued their push Self_motion against the Pusan Perimeter until they were outflanked Defending in the Battle Hostile_encounter of Inchon .

It was part of the Battle Hostile_encounter of Pusan Perimeter , and was one of several large engagements Hostile_encounter fought Hostile_encounter simultaneously .

Operating Being_in_operation as the extreme southern flank of the Pusan Perimeter , the US 25th Infantry Division placed Placing its regiments around the South Korean city of Masan , with the 24th Infantry Regiment and 5th Regimental Combat Team based in Haman and nearby Sobuk-san , and the 35th Infantry Regiment based along the Nam River to the west of the city .