Guwahati: A powerful 7.5-magnitude earthquake struck off the northeastern coast of Japan on Monday, prompting authorities to issue tsunami warnings and urge residents in coastal areas to move to safer ground.
The earthquake, which occurred at 4.52 p.m. local time, triggered alerts for possible tsunami waves of up to 3 metres along parts of northern Japan, particularly in the prefectures of Iwate Prefecture and Aomori Prefecture on the main island of Honshu, as well as the northern island of Hokkaido.
Within an hour of the tremor, tsunami waves measuring up to 80 cm were recorded, while warnings for higher waves remained in place, according to the Japan Meteorological Agency (JMA).
Several coastal towns, including Otsuchi and Kamaishi—both severely affected during the 2011 earthquake and tsunami, issued evacuation orders for thousands of residents, Japan’s public broadcaster NHK reported.
Prime Minister Sanae Takaichi said an emergency task force had been set up and appealed to residents in affected regions to evacuate promptly. “Possible damage and casualties are now being assessed,” she said.
Authorities warned that strong aftershocks could follow in the coming days and weeks.
Visuals aired on NHK showed vessels leaving ports such as Hachinohe as a precaution, while emergency alerts urged residents to evacuate. Officials cautioned that a 3-metre tsunami could inundate low-lying coastal areas and pose significant risks to life.
Rail services, including bullet trains in Aomori, were temporarily suspended following the quake, according to local reports.
The earthquake registered an “upper 5” on Japan’s seismic intensity scale, indicating strong shaking capable of making movement difficult and damaging weaker structures. The epicentre was located in the Pacific Ocean at a depth of about 10 km, the JMA said.
Japan lies along the seismically active “Ring of Fire” and experiences frequent earthquakes. The country accounts for a significant share of the world’s high-magnitude seismic activity, including the devastating 2011 earthquake and tsunami that triggered nuclear accidents at Fukushima.
Authorities said no abnormalities had been reported at idled nuclear facilities in the affected regions, including those operated by Hokkaido Electric Power Co. and Tohoku Electric Power Co.