Seoul’s Defense Ministry has estimated North Korea’s newest submarine is capable of carrying up to three short-range ballistic missiles. 

The ministry reported its analysis of North Korean submarines on Wednesday during a closed-session with the National Assembly Intelligence Committee. 

According to the parliamentary committee’s chair Lee Hye-hoon, the ministry presumed the North has built and been operating around 70 submarines since the 1970s, including variations of Russian submarines. 

The ministry estimated that the North first succeeded in test-launching submarine-launched ballistic missiles(SLBM) in 2014, adding that the latest North Korean SLBM submarines appear to be a variation of Romeo-class submarines. 

Regarding the recent violation of South Korea's air defense identification zone by Russian and Chinese aircraft, the ministry suspected that the moves were partly intended to collect information on the militaries of South Korea, Japan and the U.S.