According to MANA, A North Korean submarine fired a ballistic missile on Wednesday that flew about 500 km (311 miles) toward Japan.
The missile was fired at around 5:30 a.m. (2030 GMT) from near the coastal city of Sinpo, where satellite imagery shows a submarine base is located, officials at South Korea's Joint Chiefs of Staff and the Defence Ministry told Reuters.
"This poses a grave threat to Japan's security, and is an unforgivable act that damages regional peace and stability markedly," Japanese Prime Minister Shinzo Abe told reporters, adding that Japan had lodged a stern protest.