It was the second time in four days that the North Korean authorities, defying an escalation in international sanctions and warnings from President Trump, had launched a missile. Three short-range missiles were launched on Saturday.
The missile fired on Tuesday took off from near Pyongyang, the North Korean capital, and flew to the east, according to the South Korean military, which added that officials were analyzing the data to determine what type of missile was launched.
The Japanese government sent a text alert to citizens about the launch and advised them to take protective cover.
The missile flew over Hokkaido island in northern Japan, South Korean and Japanese officials said. It was the first time a North Korean projectile had crossed over Japan since North Korea launched a rocket over Japan in 1998, and again in 2009 carrying what the North claimed was a satellite payload.
On Tuesday, Prime Minister Shinzo Abe of Japan made a brief statement moments after it was confirmed that a North Korean missile had again passed over Japanese territory.
“We will make utmost efforts to firmly protect the lives of the people,” Mr. Abe told reporters as he entered his office for an emergency meeting, according to Reuters.