North Korea is building up its submarine force, deploying new Shark-class K-300 submarines with better performance, a longer body and higher underwater speed than the old model which infiltrated South Korean waters in 1996.
A South Korean government official said Sunday, "We've confirmed U.S. satellite images and other intelligence that the North has been building and deploying new Shark-class submarines for a few years now.
They're about 5 m longer than the old 34 m-long model and capable of traveling submerged more than 10 km/h faster."
The North has about 70 submarines and submersibles. The Shark class, which accounts for about 40 of them, is its main submarine force.