SEOUL, South Korea — The two Koreas commemorated the anniversary Friday of the outbreak of the Korean War, promoting vastly different views of the origins of the conflict that still divides their peninsula a full six decades later. The war started in the early hours of June 25, 1950, with an attack by North Korean troops. Relations are tense in the aftermath of the deadly sinking of a South Korean warship, the Cheonan, in March off the west coast of the peninsula near waters contested by the two countries, killing 46 sailors.South Korean President Lee Myung-bak used the occasion of the anniversary to urge Pyongyang to own up to the sinking."North Korea should clearly and frankly admit and apologize for its wrongdoing over its provocation" Lee said. He called on the country to assume a responsible attitude in the international community and "stop reckless military provocations."