Washington: North Korea has increased the number of underwater practices by a special unit of its military four times in 2009 from the previous year, according to US and South Korean intelligence agencies.
The South Korean government might refer to the finding as part of circumstantial evidence indicating North Korea`s involvement in the sinking of the South Korean warship in March 26 when Seoul makes an announcement on the results of its investigation into the incident, the sources said yesterday.
The announcement is expected to be made around Thursday.
The intelligence agencies have also found that North Korea has purchased underwater radio communications equipment, believed to be for use by the special military unit, from China and Russia in 2009, the sources said.
There is also information that a North Korean military commander was promoted after the March 26 incident in the Yellow Sea.
Following an unexplained explosion near the maritime border between the two Koreas, the 1,200-tonne corvette Cheonan patrol ship was split in half and sank, killing 46 sailors.
The South Korean government has not obtained evidence that clearly shows Pyongyang`s involvement, but suspicions are growing that a North Korean torpedo attack sank the ship.
North Korea has strongly denied involvement in the incident.