The North Korean flag is seen at mast past the barbed wire fencing of the North Korean embassy in Malaysia on March 27, 2017.

Japanese public broadcaster NHK on Friday sent a news bulletin that incorrectly reported had launched a missile that fell into waters east of the Japanese archipelago, issuing an apology hours later explaining it was a media training alert.

The news alert came as the United States and its East Asian allies have been on tenterhooks after Pyongyang's warning this month of a possible in what experts took to mean a possible long-range missile test.

The NHK bulletin, sent out 22 minutes after midnight on its website, read: "North Korean missile seen as having fallen into seas about 2,000 km east of Hokkaido's Cape Erimo", suggesting a flight path over Japanese territory.

At 2:28 a.m., NHK issued an apology on its website, explaining that the text was meant for training purposes and was "not true".

"We apologize to our viewers and the public," NHK said.

Warning citizens about disasters and security threats is one of the mandates for the publicly funded broadcaster, whose news casters regularly and frequently hold drills for earthquakes and other disaster coverage.

When North Korea did launch missiles that flew over , warnings spread through sirens and government-issued "J-alerts" on millions of cell phones throughout Japan, jolting some out of sleep.

NHK had also sent an erroneous news alert about a North Korean missile in error in January of last year.

North Korean leader Kim Jong Un had given the United States until the end of the year to propose new concessions in talks over his country's nuclear arsenal and reducing tensions between the adversaries.

Its last test of an intercontinental ballistic missile was in November 2017 when it fired a Hwasong-15, the largest missile it has ever tested. Pyongyang said the missile was capable of reaching all of the United States.