A powerful 7.6-magnitude earthquake struck off the eastern coast of Japan’s Aomori Prefecture late Monday, December 9, 2025, at 11:15 p.m. local time, causing widespread disruption and injuring at least 30 people across the affected region. Originating approximately 80 kilometers offshore at a depth of 50 kilometers, the seismic event led to temporary tsunami warnings for Hokkaido and the Tohoku region, observable wave height fluctuations, immediate disruptions to regional rail transport, and brief power outages before authorities eventually lifted the maritime threat early Tuesday.
The Japan Meteorological Agency confirmed the severity of the quake, which was centered near the densely populated northern Honshu area. Initial reports indicate localized damage and several injuries, primarily caused by falling debris or during emergency maneuvers. Aomori Prefecture accounted for at least 16 confirmed injuries, with the city of Hachinohe experiencing 12 cases. Additional injuries were reported in Aomori City, Goshogawara, Tohoku Town, and Rokkasho. Across the Tsugaru Strait in Hokkaido’s Hidaka area, one woman in her 70s sustained injuries after slipping on ice while exiting a vehicle at an emergency evacuation site, underscoring the secondary hazards faced by residents during mobilization.
Infrastructure and Aftershocks
The immediate aftermath brought significant infrastructural challenges. Approximately 4,200 households across Aomori and Iwate Prefectures experienced temporary electrical service interruptions. Transportation networks were severely impacted, stalling critical long-distance routes. The Tohoku Shinkansen high-speed rail service was suspended between Fukushima and Shin-Aomori stations, leaving three trains halted mid-route or at stations including Kitakami and Hachinohe.
Witness accounts from Hachinohe, located closest to the epicenter, detailed the intensity of the tremor. Shop workers described prolonged, violent shaking lasting three to four minutes, resulting in merchandise being thrown from shelves and scattered across floors. Local hotels also reported patron injuries during the initial impact.
Following the main shock, two significant aftershocks underscored the ongoing tectonic instability. A magnitude 6.6 quake occurred off eastern Honshu later Tuesday morning at 6:52 a.m., followed shortly by a magnitude 5.1 tremor off eastern Aomori at 8:59 a.m.
Safety and Nuclear Monitoring
In response to the marine threat, tsunami warnings were initially issued, with waves measuring 70 centimeters observed at Kuji Port in Iwate Prefecture and 50 centimeters at Urakawa in southern Hokkaido. These warnings were successfully downgraded and lifted as the threat subsided.
A critical focus during any major seismic event is the robust monitoring of Japan’s nuclear infrastructure. Authorities confirmed that no abnormalities were detected at nuclear facilities across Hokkaido, Aomori, Miyagi, and Fukushima Prefectures. As an extra measure of precaution, the operator of the Fukushima Daiichi plant temporarily halted the ongoing discharge of treated wastewater following the quake.
Staying Vigilant
Japanese authorities are strongly urging residents in the impacted areas to remain highly vigilant. The public is advised to anticipate and prepare for potential strong aftershocks in the coming days. Immediate actionable takeaways for residents include:
- Securing loose furniture and household items to prevent movement during tremors.
- Reviewing household emergency kits and evacuation plans.
- Preparing for swift evacuation should strong shaking be felt again.
These measures emphasize the need for continued readiness in this seismically active region. Residents should monitor official broadcasts for further safety instructions and updates regarding infrastructure resumption.