Kyodo news service reported that the quake, which struck at 3:44 amGMT Friday), hit the largest of Japan's four main islands, Honshu.

The tremor was felt in Tokyo, Yamanashi and Nagano in central Japan as well as the northeastern Yamagata and Miyagi prefectures.

The epicentre of the quake is estimated to have been in the sea off Ibaraki prefecture, north of Tokyo, the report said.

TERRA.WIRE