The quake was centred off the coast of the Fukushima region at a depth of 60 kilometres and shortly after it hit at 11:36 pm (1436 GMT) an advisory for tsunami waves of one metre was issued for parts of the coast.

There were no immediate reports of damage or injuries, but more than two million households were left without power, including 700,000 in Tokyo, electricity provider TEPCO said.

TEPCO also said in a tweet that it was checking operations at the Fukushima nuclear plant that went into meltdown 11 years ago after a huge 9.0-magnitude quake and tsunami hit off the eastern coast on March 11, 2011.

Japan sits on the Pacific “Ring of Fire”, an arc of intense seismic activity that stretches through Southeast Asia and across the Pacific basin.

The country is regularly hit by quakes, and has strict construction regulations intended to ensure buildings can withstand strong tremors.

But it remains haunted by the memory of the 2011 undersea quake in northeastern Japan that triggered a deadly tsunami and unleashed the Fukushima nuclear accident.