Powerful 7.6 earthquake hits northern Japan, tsunami warnings issued

A powerful magnitude 7.6 earthquake struck northern Japan late Monday night, prompting tsunami advisories and an unprecedented alert for a potential “mega quake” along the country’s Pacific coast.

The quake occurred at 11:15 p.m. off the eastern coast of Aomori Prefecture at a depth of 54 kilometers. Authorities initially issued tsunami warnings for Iwate Prefecture as well as coastal areas of Hokkaido and Aomori.

USGS has recorded the quakes magnitude at 7.6. However, Japanese officials have stated it was a 7.5 magnitude quake. 

At Kuji Port in Iwate, a 70-centimeter tsunami was recorded, while Hokkaido observed waves of 50 centimeters in Urakawa Town and 40 centimeters at Mutsuogawara Port.

As of 1:00 a.m., officials confirmed six injuries in Aomori, with residents hurt by falling objects or during attempts to evacuate. More than three hours after the quake, the tsunami warnings were downgraded to advisories, though authorities continue to urge residents to stay clear of the shoreline.

Japan’s Meteorological Agency has issued a rare alert warning that a much larger earthquake could follow. A potential mega quake—magnitude 8 or higher—could generate tsunamis along the Pacific coast from Hokkaido down to Chiba.

Residents in the affected areas have been urged to review evacuation routes, prepare emergency supplies, secure household furniture, and ensure access to food, water, and portable toilets. Officials say people along the Pacific coastline should remain on high alert for the next week, although no formal evacuation recommendation is currently in place.

This is the first time Japan has issued an alert under this category since it was created in 2022.

Morikubo Tsukasa, a disaster preparedness official with the Cabinet Office, said: “Based on global earthquake statistics, there is a possibility that a large-scale earthquake with a magnitude of 8 or higher could occur as a follow-up along the Japan Trench or Chishima Trench off Hokkaido. It is unclear whether such an event will happen, but everyone should take precautions to protect their lives.”