A 7.4 magnitude earthquake off north-eastern Japan near Fukushima prefecture has prompted a tsunami advisory.
The quake struck on Tuesday morning at about 06:00 local time (21:00 GMT Monday), the Japan Meteorological Agency said.
Residents were asked to seek higher ground immediately. There were reports of minor injuries.
In 2011, an earthquake and tsunami struck the same area killing thousands and destroying parts of the coastline.
The depth of the quake was estimated to be 30km (18.6 miles), the agency said.
The initial tsunami warning of possible 3m (10ft) waves was downgraded to an advisory just before 10:00 local time.
The BBC’s Rupert Wingfield-Hayes in Tokyo says tens of thousands of people have heeded evacuation warnings and headed for higher ground.
A tsunami advisory was also issued for Miyagi prefecture, where a 1.4m wave was observed at Sendai port.
A 1m wave hit the coastline near the Fukushima nuclear power plant, which was severely damaged by the 2011 quake and tsunami, the AFP news agency said.
Tokyo Electric Power has been checking the plant for damage from the latest quake.
Cabinet Chief Secretary Yoshihide Suga said at a televised news conference that the water cooling system on the third reactor of the Fukushima plant had stopped working, but there were no signs of damage and no other abnormalities at other nuclear facilities.
The plant operator later said it had restarted the cooling system, and reported only small temperature increases, within safety limits.
More than 18,000 people were killed or reported missing following the 2011 Fukushima disaster. The nuclear meltdown contaminated the surrounding area, displacing at least 100,000 people from their homes.
All reactors in the Fukushima nuclear plant were shut down following the 2011 disaster, but cooling is still needed for the used nuclear fuel stored on the site.
The US Geological Survey initially put the magnitude of Tuesday’s earthquake at 7.3 but later downgraded this to 6.9, lower than the number given by the Japanese authorities.
Damage from the quake remains unclear. Tremors were felt in Tokyo and our correspondent says buildings in the capital shook for at least 30 seconds.
Ships could be seen moving away from harbours in Fukushima prefecture, and car manufacturer Nissan suspended work at its Fukushima engine factory.
A wave of 60cm (2ft) has arrived in Onahama Port in Fukushima, Japanese broadcaster NHK reported, and another of 90cm in Soma.
The warnings were downgraded after four hours, but locals were asked to continue evacuating the area and to avoid the coastline.
Meanwhile, New Zealand authorities reported on Tuesday that an earthquake of 5.6 magnitude and 30km depth hit an area 200km north east of the capital Wellington. There were no immediate reports of deaths or injuries.
Japan lies in a particularly seismically active region and accounts for around 20% of quakes worldwide of magnitude 6.0 or more.
At least 50 people died in two quakes in the southern Kumamoto prefecture in April.
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