There were no early reports of injuries or property damage.
The Japan Meteorological Agency said a 6.2-magnitude earthquake jolted Tochigi prefecture in eastern Japan, Kyodo News reported.
Train service was temporarily suspended because of the quake, which was about 6.2 miles deep, East Japan Railway Co. said.
A 5.7-magnitude earthquake was reported in eastern Honshu, about 20 miles north-northeast of Numata, and 22 miles west-northwest of Nikko, the U.S. Geological Survey reported. The depth was 6.2 miles.
A second earthquake in Honshu, with a magnitude of 4.5 and a depth of 6.2 miles, was about 39 miles north of Maebashi, 61 miles east-northeast of Nagano and 94 miles north-northwest of Tokyo, the USGS said.
A 4.6-magnitude Honshu earthquake, with a depth of 6.1 miles, was reported 19 miles west-northwest of Nikko and 38 miles northeast of Numata, the USGS reported.