Tokyo, Japan – A powerful earthquake measuring 7.1 on the Richter scale struck southern Japan on Tuesday, July 28, 2026, prompting the Japan Meteorological Agency to issue urgent warnings of a risk of tsunami waves up to one meter high, amid a state of maximum alert in large parts of the country.
Earthquake details and operations center
The Japan Meteorological Agency reported that a powerful earthquake struck Kumamoto Prefecture between 4:27 PM and 4:45 PM local time. The epicenter was located near the city of Oki, about 4 kilometers southeast of the prefecture, at a shallow depth of less than 10 kilometers. The earthquake registered a maximum intensity of 7, the highest level on the Japanese Shindo scale, and was felt in several parts of Kumamoto Prefecture. The tremor was also felt to varying degrees in neighboring areas such as Fukuoka, Nagasaki, and Kagoshima.
Tsunami warnings and emergency procedures
Following the earthquake, official tsunami warnings were issued for the Ariake and Yatsushiro Seas, with waves expected to reach heights of approximately one meter (3.3 feet). Local authorities urged residents in vulnerable coastal areas to evacuate immediately and move to higher ground, while early warning systems were activated. Meanwhile, the Pacific Tsunami Warning Center, based in Honolulu, confirmed that there was no tsunami threat to Hawaii or American Samoa.
Field situation and infrastructure preparations
This tremor occurred in a region known for its intense seismic activity. The Japanese recall the series of devastating earthquakes that struck Kumamoto in 2016, measuring between 7.0 and 7.3 on the Richter scale. So far, there have been no immediate reports of widespread damage or injuries, while emergency teams continue their on-site assessments, particularly given the area’s importance as a major semiconductor manufacturing hub.
Aftershocks are expected, with smaller tremors exceeding magnitude 4 already recorded. Japan relies on strict building codes and sophisticated warning systems to deal with such disasters, amid official calls for citizens to follow the guidelines of the Japanese public broadcaster NHK and stay away from the coast until the danger has passed.
