North Korea fired five short-range missiles off its east coast on Sunday, in a demonstration of military muscle by the secretive state amid escalating rhetoric against the United States and South Korea.
The missiles hit the sea after about 200 km (120 miles), a South Korean defence ministry official said.
North Korea frequently fires short-range missiles off its coast as part of military drills. The United Nations imposed sanctions banning North Korea from launching longer-range ballistic missiles, but not short-range missiles.
Sunday's show of firepower marked the 67th anniversary of the formation of North Korea's armed forces by state founder Kim Il Sung, when the Korean peninsula was divided into the North and South.
North Korea in recent days also test-fired a new anti-ship cruise missile.
North Korea has increased the scale of air and naval military drills in recent weeks ahead of the annual U.S.-South Korean military exercises on the Korean peninsula, with its leader Kim Jong Un commanding his troops.
Pyongyang regularly protests over the drills, which it says are a rehearsal for war.