North Korea launched at least one ballistic missile into the sea off its east coast on Wednesday, South Korea's military said.
The launch comes after Pyongyang on Tuesday demanded that the United States and South Korea stop large-scale military exercises, calling them a provocation that may draw "more powerful follow-up measures."
Broadcaster YTN reported that an air raid warning was issued on the South Korean island of Ulleung around the time of the missile launch.
A spokesman for South Korea's military said they were checking to see whether the air raid warning was related to the missile launch.
The North Korean missile appears to have landed outside japan's exclusive economic zone. according to Kyodo News
The United States and South Korea began one of their largest combined military air drills on Monday, with hundreds of warplanes from both sides staging mock attacks 24 hours a day.
North Korea's recent missiles tests
North Korea has test-fired a record number of missiles this year and has said that a recent flurry of launches was in response to the allied drills.