TOKYO - A 6.4-magnitude earthquake jolted Japan's Hokkaido late Saturday, said the Japan Meteorological Agency (JMA).

The quake occurred at around 11:17 p.m. local time and no tsunami warnings were issued by the agency.

The epicenter was initially detected at 42.7 degrees north latitude and 143.3 degrees east longitude with a depth of 120 km.

According to the JMA, the quake was marked 5 upper at JMA Seismic Intensity in several places in Hokkaido, while the entire northeast part of Japan can felt strong tremor, including Tokyo.

No abnormalities were found in nuclear plants in the prefecture of Aomori, as well as the Tomari nuclear plant in Hokkaido, local media quoted operators as saying.

As of now, there were no reports on damage and casualty and local authorities are confirming the aftermath of the strong quake.