Japan Warns of Potential Second, Larger Tsunami After Powerful Quake

Authorities in Japan have warned that a second, potentially larger tsunami could strike following a powerful 7.5-magnitude earthquake off the country’s north-east coast.

The Japan Meteorological Agency said further seismic activity of a similar scale could occur over the coming week, noting that such warnings are standard after major earthquakes. Officials are also urging vigilance for landslides and additional aftershocks.

Residents in affected areas have been told to remain alert and stay inland until all tsunami advisories are lifted. Minoru Kihara reinforced the message, advising people not to return to coastal zones prematurely.

Initial reports indicate that around 100 households have been left without power, while some services on the Shinkansen have been temporarily suspended as a precaution.

Japan is one of the most seismically active countries in the world, accounting for more than 10% of earthquakes of magnitude six or higher globally. On average, the country experiences a magnitude-seven quake roughly once every 16 months.

The warning comes with the memory of the devastating 2011 Tohoku earthquake and tsunami still fresh. That magnitude 9.0 quake triggered a massive tsunami that killed more than 18,000 people and led to a nuclear disaster in Fukushima Prefecture.

Officials say lessons from that disaster have shaped current emergency responses, with stronger emphasis on rapid evacuation and public compliance with warnings. Residents are being urged to move to higher ground immediately if further alerts are issued, as tsunami waves can arrive in multiple surges and increase in size after the initial impact.