An earthquake with a preliminary magnitude of 6.1 jolted a wide area in northeastern Japan early Tuesday, the weather agency said. No tsunami warning was issued.

The 4:24 a.m. quake registered lower 5 on the Japanese seismic intensity scale of 7 in Aomori and Iwate prefectures, according to the Japan Meteorological Agency.

The focus of the quake was in northern Iwate Prefecture at a depth of about 80 kilometers, the agency said.

The quake caused no abnormalities at the Onagawa nuclear power plant in Miyagi Prefecture, the operator Tohoku Electric Power Co. said. The plant has been offline since the March 2011 earthquake and tsunami.

==Kyodo

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