South Korea’s Lee vows answers on Cheonan Navy ship sinking

South Korea’s President Lee Myung-bak vowed Monday to determine exactly what set off the explosion that sank a Korean Navy vessel last month, amid criticism that he had failed to act decisively and suspicion that North Korea may have been involved.

Mr. Lee avoided accusing Pyongyang, though South Korean officials have blamed an external explosion. The North has denied any part in the March 26 incident, in which the Cheonan split in two and sank, leaving 46 sailors to drown in the stern. The rest of the ship, one of a number of corvettes patrolling the Yellow Sea, stayed afloat long enough for 58 sailors to escape.

The president’s speech came as international investigators began scrutinizing the stern after it was towed to its home port on the Yellow Sea.

Investigators from the US, Australia, and Sweden said they have to examine both portions of the ship, piecing them together for clues at the port of Pyongtaek, 40 miles southwest of Seoul, before drawing conclusions about the nature of the blast. The stern of the Cheonan was lifted last Thursday by a giant crane and loaded onto a barge that towed it to Pyongtaek.

The quest for more evidence was slowed, however, when a chain with which a team was recovering the rest of the vessel broke off.

In his nationwide address, Lee pledged to “ascertain the cause” and “deal resolutely with the results and make sure such an incident does not recur."

The president parried mounting criticism as to how such an episode could have occurred, promising to “make our military stronger.” He appealed to Korean yearning for reunification, saying “the people will remember your sacrifice” whenever the two Koreans were “reunited and genuine peace and prosperity comes to this land.”

Some Korean analysts and ordinary citizens have blamed the Navy for not spotting the possible danger from North Korean submarines and floating mines along the Northern Limit Line, below which South Korea bans North Korean vessels.

South Korea’s Defense Minister Kim Tae-young has said the Cheonan may have been struck by a mine or torpedo.

North Korea issued its first formal denial of involvement in the episode on Saturday, when Pyongyang’s Korean Central News Agency quoted a military commentator as accusing South Korean “warmongers and rightist conservatives of foolishly trying to link the tragic accident to us” after failing to “pin down the cause of the sinking.”

The commentator said South Korea’s accusation was “a foolish attempt to justify its ill-natured and anachronistic North Korea policy and to evade the responsibility of driving the North-South relations to their worst.”