A moderate quake with a preliminary magnitude of 5.5 jolted Japan's Kanto region at 9:01 p.m. Friday, said the Japan Meteorological Agency.

The focus of the quake was located at a depth of 60 km to the south of Ibaraki Prefecture, some 100 km north of Tokyo, where the jolt was strongly felt.

The agency said the quake caused no concern of tsunami, and there were no immediate reports of damage or casualties.