A series of powerful earthquakes struck Japan on Monday, triggering a tsunami and knocking out power to thousands of homes.

A succession of 21 earthquakes registering 4.0-magnitude or stronger struck the coast of Ishikawa and nearby prefectures in central Japan in just over 90 minutes, the Japan Meteorological Agency said.

The strongest jolt measured 7.6 shortly after 4pm, prompting the country's first major tsunami warning since 2011, when the country experienced a 9.0-magnitude undersea quake off north-eastern Japan.

The alert caused some train services to stop, power plants to halt operations and authorities to check on nuclear reactors.

“All residents must evacuate immediately to higher ground,” national broadcaster NHK said.

The 7.6-magnitude quake was the largest in the Noto peninsula region since records began in 1885.