An earthquake with a preliminary magnitude of 7.6 hit north central Japan on Monday, public broadcaster NHK said.
The Japan Meteorological Agency issued a tsunami warning along western coastal regions of Ishikawa, Niigata and Toyama prefectures.
Tsunami of up to 5 metres high are believed to be reaching Noto in Ishikawa Prefecture, according to the weather agency.
Waves more than 1 metre high hit the coast of Wajima City in Ishikawa Prefecture, NHK reported.
Hokuriku Electric Power said it is checking for any irregularities at its nuclear power plants, NHK reported.
