Japan’s Fire and Disaster Management Agency said at least three people were seriously injured with broken bones – two women in their 80s and one in her 60s.
Fukushima prefecture said an elderly woman was hit on the head by a cupboard, and a man suffered a knee injury from glass shards while struggling with falling furniture.
The agency also reported that blazes broke out at two non-residential buildings, but they have been extinguished. No-one was hurt in the fires.
The Japan Meteorological Agency said yesterday’s earthquake was an aftershock of the magnitude 9.0 one which spawned a deadly tsunami in the same region in 2011.
The agency warned that another large quake could hit in the next few days and urged residents to remain cautious for about a week.
Yesterday’s magnitude 7.4 quake triggered moderate tsunamis, but nothing high enough to cause major damage.
It was the largest earthquake in the north-east Japan region since the 2011 quake, which killed some 18,000 people, and some large aftershocks the same day.
The quake sent residents fleeing to higher ground and triggered fears about the Fukushima nuclear power plant which was destroyed by the tsunami five years ago.
Queues of cars were seen snaking away from the coast in the pre-dawn hours after authorities issued a tsunami warning and urged residents to seek higher ground immediately. The warning was lifted nearly four hours later.
Japanese broadcaster NHK said there were reports of minor damage, and the earthquake shook buildings in Tokyo, 150 miles south-west of the epicentre.
NHK also showed one person’s video of water rushing up a river or canal, thought it was well within the height of the embankment.
It brought back memories of the 2011 disaster, when much larger tsunamis rushed up rivers and overflowed, wiping away entire neighbourhoods.
Kazuhiro Onuki is a former librarian in a town which became a no-go zone because of radiation contamination. He was staying at what he calls one of his temporary homes when yesterday’s earthquake struck.
He said he remembered “3.11” – a reference to the 11 March date of the 2011 disaster.
He added: “It really came back. And it was so awful. The sways to the side were huge.”