TOKYO -- An earthquake with a preliminary magnitude of 5.8 struck off Japan's northeastern prefecture of Fukushima on Friday (local time), according to the country's weather agency.

The temblor occurred at 00:14 am local time (1514 GMT) at a depth of 50 km, measuring lower 5 on Japan's seismic intensity scale, which peaks at 7, said Japan Meteorological Agency (JMA).

The epicenter was located off the prefecture at a latitude of 37.1 degrees north and a longitude of 141.2 degrees east.

Tremors were also felt in central Tokyo.

No casualties have been reported so far and the JMA has not issued tsunami warnings.