An earthquake registering 6,3 on the Richter scale shook the northern Japanese island of Hokkaido on Tuesday night, Kyodo news agency reported, citing the Japan Meteorological Agency.
It said there were no immediate reports of injuries or damage from the quake, which occurred at 11.09pm (2.09pm GMT). No tsunami warning was issued.
Earlier, a moderate earthquake measuring 4,6 on the Richter scale shook the central region of Niigata, which was hit by a series of strong tremors last October, the Meteorological Agency said.
There were also no immediate reports of casualties or property damage.
The focus of the quake was located about 10km beneath the surface in the region, about 200km north of Tokyo, the agency said. — Sapa-AFP