TOKYO - An earthquake with a preliminary magnitude of 6.1 struck off Japan's Fukushima prefecture at 6:23 am Thursday local time, Japan Meteorological Agency said.

The temblor was centered in waters offshore of the Fukushima prefecture, with the epicenter at a latitude of 37.1 degrees north and a longitude of 141.5 degrees east.

The focus of the quake was quite shallow under the seabed in the Pacific Ocean off Fukushima, according to the weather agency.

The quake logged 4 on the Japanese seismic intensity scale which peaks at 7 in Fukushima and Ibaraki prefectures and 3 in some other areas, and was felt in a wide range of areas including Tokyo.

So far no major damage or injuries were reported, and no tsunami warning has been issued.

No abnormalities were observed at two nuclear power plants in Fukushima near the epicenter following the quake, according to the operator Tokyo Electric Power Company Holdings Inc..

Fukushima and neighboring areas were hit by a strong earthquake with a preliminary magnitude of 7.4 early in the morning Tuesday. Over 10,000 people were evacuated.