A 5.8-magnitude quake jolted southern part of Japan's northernmost prefecture of Hokkaido at around 6:05 p.m., local time Tuesday, which could probably trigger tsunami, according to Japan's broadcaster NHK.
The epicenter was detected at 42.7 degree of north latitude and 141.3 degree of east longitude, with a very shallow depth, said the Japan Meteorological Agency.
The quake was registered at lower 5 level of Japan's seismic intensity scale of 7 in Shiraoi area.
NHK said the quake would trigger a tsunami but would not cause damage. So far there is no immediate report of damage or injuries.