TOKYO – At least four people were injured after a 7.2-magnitude earthquake struck northeastern Japan on Thursday morning, Kyodo News reported.

The temblor, revised up from a preliminary magnitude of 6.9, occurred at around 7:30 am local time off the eastern coast of Iwate prefecture at a depth of about 40 km. It measured upper 6, the second-highest level on Japan's seismic scale of 7, in Hashikami town and lower 6 in Hachinohe city, both in Aomori prefecture, the Japan Meteorological Agency (JMA) said.

An intensity of upper 6 means it is impossible to remain standing or move without crawling, and most unfixed furniture will move, and objects will topple over, according to the agency.

The earthquake also affected Hokkaido and Akita, Fukushima, Miyagi, and Yamagata prefectures, as well as Tokyo and its neighboring prefectures, according to JMA.

No tsunami advisory was issued. People in strongly affected areas were urged to remain alert for earthquakes of a similar magnitude.

There were no reports of abnormalities at the Higashidori or Onagawa nuclear power plants, located respectively in Aomori and Miyagi prefectures, or at the Fukushima Daiichi or Daini nuclear power plants in Fukushima prefecture, according to their operators.

The quake's epicenter was located at 40.2 degrees north latitude and 142.3 degrees east longitude.