North Korea has fired a missile that passed over northern Japan, the Japanese government says.
The government's J-Alert warning system advised people in the area to take precautions early on Tuesday, but public broadcaster NHK said there was no sign of damage.
The Japanese military did not attempt to shoot down the missile, which passed over Japanese territory around 6.06am local time.
The missile broke into three pieces and fell into waters about 1180 kilometres east of Cape Erimo in Hokkaido, the northernmost of Japan's main islands.
In response, Japanese Prime Minister Shinzo Abe said he would do all in his power to protect the Japanese public after the missile launch.
"We will make utmost efforts to firmly protect the lives of the people," Abe said, in brief remarks as he entered his office for emergency meetings on the missile firing.
South Korea's military said the projectile was fired from the Sunan region near the North Korean capital of Pyongyang just before 6am, local time.
Tensions had eased between North Korea and the United States after weeks of threats.
Earlier, North Korean leader Kim Jong Un had threatened to fire missiles into the sea near the US Pacific territory of Guam, and US President Donald Trump warned Pyongyang would face "fire and fury" if it threatened the US.