A powerful magnitude 7.6 earthquake shook Japan's northeast region late on Monday, prompting tsunami warnings and orders for residents to evacuate.
A tsunami as high as three metres could hit Japan's northeastern coast after an earthquake with an estimated magnitude of 7.6 occurred offshore at 11:15 p.m. (1415 GMT), the Japan Meteorological Agency (JMA) said.
Tsunami warnings were issued for the prefectures of Hokkaido, Aomori and Iwate, and a tsunami of 40 cm had been observed at Aomori's Mutsu Ogawara and Hokkaido's Urakawa ports before midnight, JMA said.
The epicentre of the quake was 80 km off the coast of Aomori prefecture, at a depth of 50 km, the agency added.
Japan is one of the world's most earthquake-prone countries, with a tremor occurring at least every five minutes.
East Japan Railway suspended some train services in the area, which was also hit by the massive 9.0-magnitude quake in March 2011.
Located in the "Ring of Fire" arc of volcanoes and oceanic trenches partly encircling the Pacific Basin, the country accounts for about 20 per cent of the world's earthquakes of magnitude 6.0 or greater.

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