At least 30 people were injured in a powerful magnitude 7.5 earthquake that struck northeastern Japan late Monday night as tsunami waves up to 70 centimeters (27.5 inches) reached the Pacific coast, local media reported on Tuesday.
The majority of injuries were reported in Aomori and Hokkaido, which are located along a major seismic trench where powerful earthquakes occur frequently as the Pacific Plate dives beneath Honshu, according to Kyodo News.
The earthquake's magnitude was initially recorded as 7.6 before being revised to 7.5.
Authorities warned that the region could experience another quake of similar or greater intensity in the coming days, and the government ordered thousands of residents to prepare for evacuation.
For the first time, the Japan Meteorological Agency (JMA) issued a special alert for the coastal areas of Hokkaido and the Sanriku coastline, which stretches across Aomori, Iwate, and Miyagi prefectures.
Following the quake, which occurred at around 11.15 p.m. local time on Monday (1415GMT), Tokyo issued tsunami warnings and advisories, urging people to seek shelter. However, the warnings were later lifted.
The earthquake was measured at a depth of 53.1 kilometers (nearly 33 miles) off the coast of northern Aomori prefecture.
Prime Minister Sanae Takaichi urged residents to remain vigilant, follow updates from local officials, and take precautions such as securing unstable household items.
"The government asks residents to continue social and economic activities while maintaining a readiness to evacuate immediately if any shaking is felt," Takaichi told reporters.
Several moderate aftershocks, ranging from magnitude 5.0 to 6.6, were also reported in the hours following the main quake, according to the US Geological Survey.
Following the massive earthquake, tsunami warnings had been initially issued for prefectures Aomori, Iwate, and Hokkaido's Central Pacific Coast, with tsunami advisories for prefectures Miyagi, Fukushima, and Hokkaido's West and East Pacific Coast.
Later, tsunami warnings for all regions were downgraded to an advisory level, while the earthquake also caused power outages in about 2,700 homes in Aomori.
No abnormalities have been reported by nuclear plants in Hokkaido or in the northeastern prefectures of Aomori, Miyagi, and Fukushima.
