 Complete the following phrase:  In early 1950, prior to the North Korean Peoples Armys southward advance across the 38th parallel, the North frequently launched small offensives at the border and inserted thousands of guerillas infiltrators into the South as far as Jeju Island in hopes of achieving the overthrow of President Syngman Rhee and the imposition of a communist government. After a number of Republic of Korea Army ROKA counterinsurgency successes, the North Koreans waged a final attempt at inciting revolution by sending two battalion-sized units of guerillas under the commands of Kim Sang-ho and Ki Moo-hyon. The first unit was, over the course of several engagements with the ROKA 6th Division, destroyed with only one survivor. The second was also annihilated by a two-battalion hammer-and-anvil maneuver by units if the ROKA 6th Division. The KPA guerillas lost 584 480 killed, 104 captured and the ROKA troops reported 69 killed and 184 wounded. It would prove to be the last major effort of the communist north to annex the south until 