Japan earthquake kills four and knocks out power

A powerful earthquake struck off the coast of Fukushima in northern Japan on Wednesday night, killing four people and injuring 97.

The 7.4 magnitude quake smashed furniture and knocked out power as a small tsunami reached the shore.

It struck in the area of northern Japan, devastated by a deadly 9.0 quake and tsunami 11 years ago when nuclear reactor meltdowns spewed radiation that still makes some parts uninhabitable.

Prime Minister Fumio Kishida told a parliamentary session four people died during the quake. The cause of their deaths was being investigated. He said 97 others were injured.

A man in his 60s in Soma city died after falling from the second floor of his house while trying to evacuate. A man in his 70s suffered a heart attack, Kyodo News reported.

The Japan Meteorological Agency lifted its low-risk advisory for a tsunami along the coasts of Fukushima and Miyagi prefectures early on Thursday. Tsunami waves of 30 centimetres reached shore in Ishinomaki, about 390 kilometres north-east of Tokyo.

The agency upgraded the magnitude of the quake to 7.4 from the initial 7.3, and the depth from 60 kilometres below the sea to 56 kilometres.

Footage showed broken walls and shards of glass scattered on the street near the main train station in Fukushima city. Roads were cracked and water poured out from pipes underground. Furniture and appliances smashed to the floor in apartments and cosmetics and other merchandise at convenience stores fell from shelves.

In Yokohama, near Tokyo, an electric pole nearly fell.

More than 2.2 million homes were temporarily without electricity in 14 prefectures, including the Tokyo region, but power was restored at most places by the morning.

The quake shook large parts of eastern Japan, including Tokyo, where buildings swayed violently.

A Tohoku Shinkansen express train partially derailed between Fukushima and Miyagi due to the quake, but nobody was injured, Prime Minister Fumio Kishida said.

He told reporters the government was assessing the damage and promised to do its utmost for rescue and relief operations.

“Please first take action to save your life,” Mr Kishida tweeted.