An earthquake with a preliminary magnitude of 6.2 struck off Japan's northernmost main island of Hokkaido on Sunday, the weather agency said, with no tsunami warning issued.

The quake registered a lower 5 on the country's seismic intensity scale of 7 in Chitose and other parts on the southern coast of the prefecture around 6:55 p.m., the Japan Meteorological Agency said. Sapporo, Hakodate and some other cities marked 4 on the scale.

There were no immediate reports of casualties due to the earthquake, police and other local authorities said.

The quake occurred at a depth of 136 kilometers in waters off Urakawa, southern Hokkaido, and also shook a wider region in northeastern Japan.

No abnormalities were detected at nuclear facilities in the affected area, including the Tomari nuclear power plant in Hokkaido and nuclear fuel cycle facilities in Aomori Prefecture, their operators said.

Hokkaido Railway Co. suspended operations on some local lines, while subway train schedules were disrupted in Sapporo.

Bullet trains on the Hokkaido, Tohoku, Joetsu and Hokuriku Shinkansen lines continued to operate as usual, according to East Japan Railway Co. and Hokkaido Railway.

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