Powerful Magnitude 7.1 Earthquake Strikes Kumamoto, Japan
A strong earthquake measuring magnitude 7.1 on the Japan Meteorological Agency scale struck southern Japan’s Kyushu island on Tuesday afternoon, registering the maximum intensity of 7 in parts of Kumamoto Prefecture and triggering a tsunami advisory for nearby coastal waters.
The quake hit at approximately 4:27 p.m. Japan Standard Time with its epicenter in the Kumamoto region, near the cities of Uki and Uto, at a shallow depth of about 10 kilometres. The U.S. Geological Survey recorded a slightly lower moment magnitude of 6.8.
Maximum shaking of shindo 7 – the highest level on Japan’s intensity scale — was observed in Uki City and Hikawa Town. Stronger shaking of shindo 6-plus was recorded in parts of Kumamoto City, Yatsushiro, Uto, Mashiki and Misato. Intensities of 5 or higher were widely felt across Kumamoto Prefecture and in neighbouring areas of Nagasaki, Kagoshima, Fukuoka, Saga, Oita and Miyazaki.
The Japan Meteorological Agency issued a tsunami advisory shortly after the mainshock for the Ariake Sea and Yatsushiro Sea, warning of possible waves up to about one metre. Residents and visitors along those coasts were urged to stay away from the shoreline. The Pacific Tsunami Warning Center later assessed that any broader tsunami threat had passed, with only possible minor sea-level fluctuations remaining near the source.
The Prime Ministers office has also issued an advisory, asking residents to cooperate with local authorities and provide information to aid rescue efforts.
Kyushu Electric Power reported power outages affecting roughly 48,300 households in Kumamoto Prefecture. Railway operator JR Kyushu suspended services, including high-speed Shinkansen trains, across the affected region. The utility confirmed there were no irregularities at its Sendai and Genkai nuclear power stations. Companies with manufacturing facilities in the broader area, including Sony and TSMC, said they were assessing the situation at their plants.
As of early evening local time, Japan’s Fire and Disaster Management Agency reported that human casualties and residential damage remained under confirmation, with numerous emergency calls received in the hardest-hit areas. No fires or damage to critical facilities had been confirmed at that stage. Kumamoto Prefecture activated its disaster response headquarters immediately, and the national agency established its own crisis unit while requesting emergency support from neighbouring prefectures.
Aftershocks continued in the hours following the main event, including tremors registering up to shindo 5. Authorities urged residents to remain vigilant.
The tremor struck a region still marked by the devastating April 2016 Kumamoto earthquakes, which killed 278 people and caused extensive damage, including to Kumamoto Castle, which remains under long-term restoration.
Japan sits atop the Pacific Ring of Fire and experiences frequent seismic activity. Officials continue to assess infrastructure while monitoring aftershocks and any residual coastal effects. Further updates on casualties, damage and recovery efforts are expected as emergency teams complete surveys.
