Powerful 7.4-magnitude earthquake off Japan triggers tsunami alert

A strong 7.4-magnitude earthquake struck off Japan’s northern coast on Monday, prompting the issuance of a tsunami alert and triggering emergency monitoring across vulnerable coastal regions.

According to the Japan Meteorological Agency, the earthquake occurred at approximately 4:53 pm local time off the Sanriku coast, a region in northern Japan historically prone to seismic activity. The tremor originated at a shallow depth of about 10 kilometres beneath the seabed, increasing the likelihood of tsunami generation.

Tsunami alert issued

Japan’s public broadcaster NHK reported that tsunami waves of up to 3 metres (around 10 feet) could reach parts of the northern coastline shortly after the quake.

Authorities issued alerts urging residents in coastal areas to remain vigilant and prepare for possible evacuation, particularly in low-lying regions and areas close to the shoreline.

Emergency response activated

Emergency services and disaster management agencies were placed on high alert, with monitoring systems tracking sea-level changes and potential wave activity. Local administrations began issuing advisories through public announcement systems and mobile alerts.

Railway services in some areas were temporarily halted as a precautionary measure, while nuclear facilities in the region were reported to be under routine safety checks.

High-risk seismic zone

Japan is located along the Pacific “Ring of Fire”, one of the most earthquake-prone zones in the world, where tectonic plate movements frequently trigger seismic events.

The Sanriku coast, in particular, has a history of devastating earthquakes and tsunamis, including the 2011 disaster that caused widespread destruction and loss of life.

There were no immediate reports of casualties or major damage, but authorities said assessments were ongoing.

Residents have been advised to stay away from coastal areas until the alert is lifted, as aftershocks and subsequent waves remain a possibility following a quake of this magnitude.

Further updates are awaited as officials continue to evaluate the situation and ensure public safety.