M20 recoilless rifles in action. These weapons were used at the Notch against North Korean machine gun positions.

The Battle of the Notch was an engagement between United States and North Korean forces early in the Korean War on August 2, 1950 in southern South Korea. The fight ended in a victory for the United States after North Korean forces attempting to assault the US position were blocked and repelled repeatedly, suffering heavy casualties.

Reeling from the Hadong Ambush and being driven from the city of Chinju, the US Army’s 19th Infantry Regiment, 24th Infantry Division scrambled to protect the pass into Masan, the final South Korean city before the Naktong River, where the UN was holding its Pusan Perimeter in place. North Korean and US forces unexpectedly ran into one another and a confused battle ensued. American forces were better equipped with heavy weapons and armor thanks to newly arrived equipment in the country, and their better ground during the battle allowed them to repel North Korean advances.

The North Korean force eventually withdrew after several unsuccessful attacks, having suffered heavy casualties. As it was disengaging from Masan, US Air Force aircraft caught the North Korean truck columns as they were retreating, inflicting significant damage on them and producing further casualties. This fight, with a number of smaller engagements in the region, effectively stopped the North Korean offensive on the southern flank of the Pusan Perimeter. It also gave both sides a reprieve from the fighting to resupply and re-enforce before engaging in the Battle of Pusan Perimeter shortly after.

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