North Korea has fired "several" banned ballistic missiles that flew about 1000km into waters off its east coast, South Korea's military says, in an apparent reaction to huge military drills by Washington and Seoul that Pyongyang insists are an invasion rehearsal.
Japanese Prime Minister Shinzo Abe said the reclusive country fired four ballistic missiles, three of which fell into Japan's exclusive economic zone.
Tokyo had "lodged a stern protest with North Korea," Abe told reporters.
The launch was "a grave threat to our country's national security," the government's spokesman Yoshihide Suga told a news conference.
It was not immediately clear what type of missile was fired or the exact number.