North Korea has launched a submarine capable of firing ballistic missiles, South Korean media reported Sunday, quoting South Korean government sources.
The Yonhap News Agency said North Korean engineers reverse-engineered a Soviet-era Golf-class diesel submarine to build a copy with a suspected displacement of 2,000 to 2,500 tons.
The Soviet vessel was built in 1958. North Korea acquired it in the early 1990s, and dismantled it to study how to build submarines capable of firing ballistic missiles.
North Korea has yet to mount missile tubes on the submarine but has reportedly carried out dozens of missile tube tests both on land and at sea.
Furthermore, it is thought to be trying to build nuclear warheads small enough to fit on a submarine-launched rocket, potentially posing a new security threat to South Korea, Japan and the United States.
South Korean military experts believe North Korea would be able to install the missile tubes in the new submarine within one to two years.
According to South Korea's Defense Ministry and other sources, North Korea has about 70 submarines, including around 20 1,800-ton Romeo-class vessels and small submersibles of about 325 and 130 tons.
The South Korean government believes a small North Korean submarine fired the torpedo that sank a South Korean warship in the Yellow Sea in March 2010.