S. Korea searches for missing sailors following mystery sinking

South Korean authorities are stepping up the search for more than 40 missing sailors after a naval ship sank with 104 crew on board.

According to South Korean authorities, 58 sailors from the “Cheonan” have been rescued while 46 remain unaccounted for, AP reported.

South Korean President Lee Myung-bak ordered officials to investigate the cause of the sinking and take all possibilities into consideration, presidential spokesperson Kim Eun-hye was quoted as saying.

According to latest media reports in South Korea, some senior officials suggested the sinking could have been an accident, not a military strike from North Korea as was earlier speculated.

Shortly after the accident, South Korea's official Yonhap news agency said that an explosion was to blame and the military had not ruled out an attack by North Korean forces.

The news broke shortly after North Korea announced it was fortifying its naval force in response to joint US-South Korean military exercises which were held in March 2010.