Japan’s Meteorological Agency has issued its first-ever “megaquake” advisory following an earthquake that struck off Aomori Prefecture on Monday, December 9, 2025. The advisory warns of the potential for a magnitude eight or higher tremor with tsunami risks along the coastline and remains in effect until December 16.
The initial quake injured 51 people, including seven with severe injuries. Chief Cabinet Secretary Minoru Kihara stated: “Based on the instruction from the prime minister, we are mobilizing all resources for assessing damage, conducting search-and-rescue operations, and implementing emergency disaster relief measures under the policy of prioritizing human life.”
Approximately 800 homes lost power in the affected region, with Shinkansen bullet trains suspended. Power was restored by Tuesday morning. Some 200 passengers were stranded overnight at New Chitose Airport due to terminal building damage, and about 480 residents sought shelter at Hachinohe Air Base.
Municipalities across seven prefectures—Hokkaido, Aomori, Iwate, Miyagi, Fukushima, Ibaraki, and Chiba—have activated emergency protocols, urging residents to prepare emergency kits and stay vigilant. Authorities recommend sleeping in day clothes and remaining with vulnerable family members for swift evacuation if necessary.
The latest earthquake, which included a magnitude-5.7 aftershock on Wednesday, has caused no reported fatalities but prompted widespread readiness measures nationwide.
