North Korea has deployed a new generation of high-speed, radar-evading warship designed to infiltrate special forces into South Korean territory.
The Very Slender Vessel sits low in the water and is designed to pierce waves instead of riding over them. Capable of travelling at nearly 60 mph, the craft are armed with heavy machine guns and torpedoes, with the JoongAng Ilbo quoting South Korean military officials as saying the ships pose a "new threat" to its security.South Korea first learned that its neighbour was developing VSVs late last year when satellites caught images of early tests with the new technology in the East Sea.
Intelligence officials in Seoul now estimate that at least seven of the vessels have been put into service on the west coast of the peninsula, with one of the craft recently sighted off Yongmae Island.
The island is just 7 miles from the South's Yeonpyeong Island, which North Korean artillery batteries bombarded in November 2012, killing two civilian residents and two military personnel.
Yongmae is also about three miles from the disputed sea border between the two Koreas, although Pyongyang refuses to accept the frontier line. The area has been the scene of repeated clashes between the two nations' navies.
"The North appears to have decided to deploy the VSVs at its Yellow Sea Fleet Command in order to strengthen its capabilities in western waters and to infiltrate the South's Baeknyeong Island in times of emergency", a government official told the JoongAng Ilbo.
Deployment of the VSVs coincides with the North carrying out extensive fortification work on the nearby island of Gal, with analysts suggesting that new weapons emplacements are designed to house rocket launchers.
North Korea has previously used midget submarines to infiltrate agents into South Korean territory, while Pyongyang has invested heavily on a fleet of large hovercraft designed to deliver assault troops to beaches.
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