A powerful earthquake with a magnitude of 7.3 jolted Japan’s northeast coast on Wednesday, shaking buildings as far away as Tokyo where it left hundreds of thousands without power, and reviving memories of a devastating quake 11 years earlier.

The tremor hit off the coast of Fukushima prefecture, some 275km northeast of Tokyo and at a depth of 60km, the Japan Meteorological Agency (JMA) said.

It triggered a fire alarm at a turbine at the crippled Fukushima Daiichi plant, authorities said, adding that they were checking the situation. That plant was devastated by a magnitude 9 earthquake and following tsunami in March 2011.

Authorities issued a tsunami warning for the region of as high as 1 metre , with public broadcaster NHK reporting waves of 20cm in some places.

Prime Minister Fumio Kishida told reporters his government was assessing the extent of any damage.

Tokyo Electric Power Company said that around 2 million households were without power, including 700,000 in the capital.