Japan has cautioned residents to brace for “strong quakes for a week” after a powerful 7.6-magnitude earthquake struck off the country’s northern coast late Monday, according to the US Geological Survey. This marks the first time Japan has issued an offshore quake alert for the Hokkaido–Sanriku region, highlighting the heightened seismic risk.

The quake occurred at around 11:15 p.m. local time (1415 GMT) and was recorded at a depth of 53.1 kilometers off the coast of Aomori Prefecture, the USGS reported. Following the initial jolt, Japan experienced two additional tremors measuring 5.5 and 5.0, intensifying concerns across the region. The Japan Meteorological Agency later revised the main quake’s magnitude to 7.5, according to the Ankara News Agency.

In the immediate aftermath, Tokyo issued tsunami warnings and advisories, urging coastal residents to evacuate to higher ground. Although the warnings were later lifted, authorities remained vigilant. Initial tsunami alerts were issued for Aomori, Iwate, and Hokkaido’s Central Pacific Coast, with advisories extended to Miyagi, Fukushima, and Hokkaido’s western and eastern coasts. These were subsequently downgraded to advisory levels as wave activity stabilized.

Reported tsunami waves reached 70 cm in Iwate, 50 cm in Hokkaido, and 40 cm in Aomori, prompting temporary coastal closures. In Aomori, a road collapse left one person injured, while two people in Hokkaido sustained injuries after falling during the violent tremors.

The earthquake disrupted power in about 2,700 homes in Aomori, and two separate fires were reported in the area. Authorities are still investigating whether the blazes were triggered by the seismic shock. Meanwhile, no abnormalities have been reported at nuclear power facilities in Hokkaido, Aomori, Fukushima, or Miyagi, easing early fears of potential radiation risks.

Transport services also faced interruptions, with Tohoku Shinkansen bullet train operations halted across northeastern Japan. Emergency responders and local authorities are conducting safety checks before fully restoring services.

The government swiftly activated an emergency response room at the Prime Minister’s Office, coordinating rescue, assessment, and recovery efforts. The office communicated developments through the social platform X, underscoring the need for public caution as aftershocks continue.

Japan, located on the Pacific Ring of Fire, remains one of the world's most earthquake-prone nations, and officials are urging residents in the affected regions to stay alert in the days ahead.

BOB Post