January 25, 1951, the American Far East Command (FEC) created its first advanced base in North Korea to undertake guerilla warfare. In Paengyong, the first guerrilla forces were formed, educated, and armed. They proved to be a powerful unit for striking and destroying North Korean and Communist Chinese soldiers in rear regions, thanks to logistical assistance, supplies, training, and guns given by their US Army commanders. The guerrillas did a good job of delivering deep information and keeping the Communist troops off balance for the rest of the battle. While most of their activities took place along North Korea’s west coast, they also acted along the east coast, with a station in Wonsan Harbor until the Armistice.