After the outbreak of the war by traitor Syngman Rhee, the puppet army and police on Jeju Island brutally killed hundreds of islanders who were preliminarily arrested only in South Jeju County till August according to the list premeditatedly worked out under the pretext of those suspects of the April 3 uprising.

In 2007 the south Korean Committee for Settling the Past History for Truth and Reconciliation defined the killing as an illegal massacre by the authorities and, afterwards, the bereaved families filed a suit against the authorities for reparation.

The court authorities admitted the illegality of the massacre and ruled the "government" should make reparation.