North Korean leader Kim Jong Un supervised missile tests that simulated nuclear counterstrikes against U.S. and South Korean forces, state media said on Friday. The tests of short-range ballistic missile systems from North Korea's eastern coastal city of Wonsan were detected by South Korea's military the day before.

North Korea fired several short-range ballistic missiles into the sea between Korea and Japan on Thursday morning, Seoul's military said, in what officials characterized as a possible test ahead of export to Russia.

North Korea launched a series of short-range ballistic missiles during a nuclear counterstrike drill overseen by leader Kim Jong Un, in what state media said was a response to recent nuclear exercises by the United States and South Korea.