Japan has urged residents to “evacuate immediately” after a 7.6 magnitude earthquake struck the central region.
A major tsunami warning was issued for the coastal Noto area in Ishikawa, warning of waves as high as 5m.
Authorities also issued tsunami warnings for the neighbouring Niigata and Toyama prefectures, where they said waves could reach 3m.
Public television flashed “EVACUATE” in big letters, urging residents to flee to higher ground despite the cold.
An NHK presenter urged affected viewers: “We realise your home, your belongings are all precious to you, but your lives are important above everything else. Run to the highest ground possible.”
People have also posted videos of their homes and subway trains shaking during the earthquake on Monday, New Year’s Day.
A succession of 21 earthquakes registering 4.0 magnitude or stronger struck central Japan in just over 90 minutes on Monday, the Japan Meteorological Agency (JMA) said. The strongest tremor hit at 16:10 local time (07:10 GMT), measuring 7.6.
Several local media reports said this was the first time a “major tsunami warning” was issued since 2011, when a powerful earthquake tore through north-eastern Japan and unleashed waves of up to 40m high.
Japan is one of the most seismically active nations on Earth, owing to its location on the so-called Pacific Ring of Fire, where many tectonic plates meet. The constant threat of earthquakes has led Japan to develop one of the world’s most sophisticated tsunami warning systems.