At dawn on Sunday, 25 June 1950, the Korean People's Army crossed the 38th parallel behind artillery fire. The KPA justified its assault with the claim that ROK troops had attacked first, and that they were aiming to arrest and execute the "bandit traitor Syngman Rhee". Fighting began on the strategic Ongjin peninsula in the west. There were initial South Korean claims that they had captured the city of Haeju, and this sequence of events has led some scholars to argue that the South Koreans actually fired first.

Who provoked a conflict by crossing the 38th parallel?