Tsunami alerts issued along northeast coast
Japanese authorities have warned that the risk of a major earthquake in the coming week is elevated following a powerful 7.7-magnitude undersea quake off the country’s northeast coast.
The tremor struck at a depth of 10 kilometers in waters off Iwate prefecture, roughly 530 kilometers north of Tokyo, prompting evacuation orders and tsunami warnings across parts of Honshu and Hokkaido. Coastal residents were urged to move to higher ground amid forecasts of waves potentially reaching 3 meters.
The largest recorded waves measured about 80 centimeters, but the Japan Meteorological Agency cautioned that stronger shaking could follow. Officials later said the probability of a quake measuring 8.0 or higher is now “relatively higher than during normal times.”
Transport disruptions and precautionary evacuations
Tremors were felt as far south as Tokyo, while tsunami alerts remained in effect in parts of Hokkaido for several hours after the quake struck at 16:52 local time.
Residents described swift reactions to emergency alerts. Local authorities used loudspeakers to instruct communities to stay vigilant and avoid coastal areas. Office workers in some regions were permitted to leave early as a precaution.
According to Cabinet Secretary Minoru Kihara, several bullet train services were disrupted and around 100 homes temporarily lost power. No major injuries or widespread structural damage were immediately reported.
The tsunami warning, the second-highest level in Japan’s three-tier alert system, advised people to evacuate coastal and riverside areas and remain in safe locations until the notice was lifted. It was later downgraded before being fully withdrawn shortly before midnight.
Memories of 2011 heighten concern
The warnings have revived memories of the catastrophic 9.0-magnitude earthquake in March 2011, which triggered a devastating tsunami and led to the nuclear disaster at Fukushima. More than 18,000 people lost their lives in that tragedy.
Japan sits along the seismically active Ring of Fire and experiences approximately 1,500 earthquakes annually, accounting for about 10% of the world’s quakes measuring 6.0 or higher. As a result, emergency preparedness systems and public alert mechanisms are highly developed.
Prime Minister Sanae Takaichi urged residents to remain cautious and move to “higher, safer places” if further warnings are issued. Authorities stressed that tsunami waves can arrive in multiple surges and emphasized the importance of not returning to coastal areas prematurely.
Seismologists continue to monitor aftershock activity, warning that conditions remain unstable in the affected region.
