SEOUL, Oct 4 (AFP) - North Korea fired a ballistic missile over Japan for the first time in five years on Tuesday (Oct 4), prompting a warning for residents to take cover and a temporary suspension of train operations in northern Japan.

South Korea's Joint Chiefs of Staff (JCS) and the Japanese coast guard reported on the missile test, which was launched over North Korea's east coast.

The Japanese government warned citizens to take cover as the missile appeared to have flown over and past its territory before falling into the Pacific ocean. It said it did not use any defence measures to destroy the missile, which was the first to fly over or past Japan from North Korea since 2017.

"North Korea's series of actions, including its repeated ballistic missile launches, threatens the peace and security of Japan, the region, and the international community, and poses a serious challenge to the entire international community, including Japan," Japan's top government spokesperson Hirokazu Matsuno, said in a brief news conference.

Speaking to reporters shortly afterward, Prime Minister Fumio Kishida called North Korea's actions "barbaric", and that the government would continue to gather and analyse information.

South Korea's JCS said it appeared to have been an intermediate-range ballistic missile (IRBM) launched from North Korea's Jagang Province. North Korea has used that province to launch several recent tests, including multiple missiles that it claimed were "hypersonic".

TV Asahi, citing an unnamed government source, said North Korea might have fired an intercontinental ballistic missile (ICBM) and it fell into the sea about 3,000km from Japan.

The latest launch was Pyongyang's fifth in 10 days, amid military muscle-flexing by the United States and South Korea, which conducted trilateral anti-submarine exercises last week with Japanese naval forces.

South Korea staged its own show of advanced weaponry on Saturday to mark its Armed Forces Day, including multiple rocket launchers, ballistic missiles, main battle tanks, drones and F-35 fighters.

The test prompted East Japan Railway Co to suspend its train operations in the northern regions, Japanese broadcaster NHK reported.

The North has completed preparations for a nuclear test, which it might look to undertake sometime between China's Communist Party Congress this month and US mid-term elections in November, South Korean lawmakers said last week.