Overview
- The offshore earthquake struck around 23:15 local time with a JMA provisional magnitude of 7.5–7.6 at roughly 50–54 km depth, producing intensity 6-upper shaking in Hachinohe.
- Tsunami warnings for parts of Hokkaido and the Tohoku coast were downgraded overnight and lifted by early morning after waves of up to 70 cm were recorded at Kuji port.
- The Japan Meteorological Agency and the Cabinet Office issued the Hokkaido–Sanriku aftershock advisory for the first time, asking residents to stay ready to evacuate during the next week.
- Officials said the chance of a far larger quake is small but cannot be ruled out, urged normal operations to continue, and cautioned against misinformation and panic buying.
- The government prioritized life‑saving and rescue efforts, sent a Cabinet Office survey team to assess damage, and NHK reported at least 33 injuries and 14 damaged buildings in Aomori Prefecture.