The Japan Meteorological Agency said there was no threat of a tsunami. There have been no reports of damage or casualties. Tremors were felt across 14 prefectures, including in the nation's capital city of Tokyo.
There have also been no reports that the crippledFukushima Daiichi nuclear plant in the Fukushima Prefecture has been affected. In 2011, the nuclear power plant was hit by a 14-meter tsunami wave, triggered by a 9.0 magnitude earthquake.
The tsunami caused a meltdown of several of the plant's reactors and a major leakage of radioactive materials. A complete elimination of its consequences is expected to take up to 40 years.