TOKYO, Jan. 8 (Xinhua) -- An earthquake with a magnitude of 6.4 struck off Japan's Kagoshima Prefecture, in the southernmost part of Japan's southwestern Kyushu island, on Tuesday, the Japan Meteorological Agency (JMA) said.

The JMA revised its preliminary report from magnitude 5.9 to 6.4, minutes after the quake struck.

The temblor occurred at 9:39 p.m. local time (1239 GMT), with its epicenter at a latitude of 30.6 degrees north and a longitude of 131.2 degrees east, and at depth of 30 km.

The quake logged 4 in some parts of Kagoshima Prefecture on the Japanese seismic intensity scale which peaks at 7.

So far no tsunami warning has been issued.