Japan Issues Tsunami Warning After Major Earthquake; Second Quake Expected

Tue Apr 21 2026 18:07:13 GMT+0000 (Coordinated Universal Time)

Authorities in Japan remain on high alert following a powerful 7.7 magnitude earthquake, warning of possible larger aftershocks and the potential for heightened tsunami threats.

Following a 7.7 magnitude earthquake off Japan's northeastern coast, officials warned of the possibility of further significant seismic activity. The quake prompted evacuations and tsunami warnings for coastal regions, although the initial tsunami alerts were later lifted. The nation is still reeling from the memories of past disasters, particularly the catastrophic events of 2011. As residents remain alert, authorities advise on the increased risk of a subsequent quake measuring 8.0 or higher.

Officials in Japan have warned of an increased risk of a huge earthquake in the next week after a 7.7 magnitude quake struck off the north-east coast, triggering an evacuation order and warnings of 3m (10ft) tsunami waves.

Thousands of people were told to leave coastal areas for higher ground after the quake in waters off Iwate prefecture, located 530km (330 miles) north of the capital Tokyo. The biggest tsunami waves recorded were 80cm, but warnings and advisories were lifted hours after the quake.

However, Japan's meteorological agency has cautioned that quakes causing even stronger shaking could occur in the next week, potentially generating bigger waves. Authorities reported the risk of a quake measuring 8.0 magnitude or higher was relatively higher than during normal times.

Japan remains vigilant, haunted by the memory of the catastrophic 2011 quake that led to a devastating tsunami, killing over 18,000 people and causing a nuclear accident at Fukushima. After this week's undersea quake, recorded at a depth of 10km, alerts were issued advising residents in the regions closest to the epicenter—on Honshu and Hokkaido—to remain cautious.

Tremors were even felt as far away as Tokyo, and although tsunami alerts persisted in Hokkaido for several hours after the initial quake, residents were urged to stay informed and heed safety warnings.

Some bullet trains experienced disruptions, and approximately 100 homes lost power according to Japan's Cabinet Secretary Minoru Kihara, who reported no immediate major damage or injuries. Train services resumed that same night.