Did You Know
Japan has lifted the tsunami advisories issued after a 7.4 magnitude earthquake hit its eastern coast.
The quake struck near Fukushima at about 06:00 local time (21:00 GMT Monday), triggering initial warnings of 3m (9.8ft) high waves. The waves which eventually hit the coast were much smaller.
Thousands were asked to evacuate the area and minor injuries were reported.
An earthquake and tsunami struck the area in 2011 killing 18,000 people.
That quake, one of the most powerful ever recorded, also caused a meltdown at the Fukushima nuclear power plant, where a massive clean-up operation is still going on.
Officials have said there is no sign of damage to the plant this time.
The US Geological Survey initially put the magnitude at 7.3 but later downgraded this to 6.9, lower than the number given by the Japanese authorities.
The Japan Meteorological Agency (JMA) said in its latest update that no tsunami damage is expected, although there may be slight changes to the sea level.
The agency has also said the latest tremor was an aftershock of the 2011 quake.
A spokesman quoted by Japan Times said the area was still generating at least one earthquake of 7.0 magnitude or more each year.
Heading for higher groundThe depth of Tuesday's quake was estimated to be 30km (18.6 miles), the JMA said.
Strong tremors could be felt as far away as the capital, Tokyo, 100 miles south of Fukushima prefecture. Buildings in the capital shook for at least 30 seconds.
The BBC's Rupert Wingfield-Hayes in Tokyo says tens of thousands of people have heeded evacuation warnings and headed for higher ground.
Ships could be seen moving away from harbours in Fukushima prefecture and car manufacturer Nissan suspended work at its Fukushima engine factory.
A 1m wave hit the coastline near the Fukushima nuclear power plant, but Cabinet Chief Secretary Yoshihide Suga said at a televised news conference that "there was no problem".
All reactors were shut down in 2011, but cooling is still needed for the used nuclear fuel stored on the site.
Mr Suga said the water cooling system on the third reactor had stopped working, but there were no signs of further damage or abnormalities.
Tokyo Electric Power, which operates the plant, later said it had restarted the cooling system, and reported only small temperature increases, within safety limits.
A wave of 60cm (2ft) arrived in Onahama Port in Fukushima, Japanese broadcaster NHK reported, and another of 90cm in Soma.
There so far appears to have been only minimal damage, and our correspondent says tsunami defences rebuilt since 2011 have ensured that waves have not caused flooding nor damage.
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.
Meanwhile, an earthquake of 5.6 magnitude and 30km depth hit an area 200km north east of the New Zealand capital, Wellington. There were no immediate reports of deaths or injuries.
Geoscience Australia senior seismologist Hugh Glanville told New Zealand's Stuff news website that the quakes "are not directly related".
"One did not cause the other, but are both a result of shifts in the Pacific plate," he said.