Many injuries were reported from Pacific coastal areas of the main Honshu island and the capital Tokyo, police said, while TV footage showed widespread flooding in the area. One person was confirmed dead.
A powerful 10-metre (33 feet) wall of water was reported in Sendai in northeastern Miyagi prefecture, media reported after a four-metre wave hit the coast earlier.
Helicopter footage showed massive inundation in northern coastal towns, where floods of black water sent shipping containers, cars and debris crashing through towns.
Mud waves were shown racing upstream along the Natori river in Sendai city, blanketing farm fields.
In the capital, where millions evacuated strongly swaying buildings, multiple injuries were reported when the roof of a hall collapsed during a graduation ceremony, police said.
The first quake struck just under 400 kilometres (250 miles) northeast of Tokyo, the US Geological Survey said. It was followed by several aftershocks, one as strong as 7.1.
“We couldn’t escape the building immediately because the tremors continued... City officials are now outside, collecting information on damage,” she told AFP by telephone.
The quake, which hit at 14:46 pm (0546 GMT) and lasted about two minutes, strongly rattled buildings in greater Tokyo, the world’s largest urban area and home to some 30 million people.
Japan sits on the “Pacific Ring of Fire”, which is dotted with volcanoes, and Tokyo is situated in one of its most dangerous areas.
“An earthquake of this size has the potential to generate a destructive tsunami that can strike coastlines near the epicentre within minutes and more distant coastlines within hours,” the centre said in a statement.
The quake sent the Nikkei share index plunging at the close while the yen fell sharply against the US dollar.
|Area mightbe hit by tsunami in hourly counting.|
The mega-city of Tokyo sits on the intersection of three continental plates — the Eurasian, Pacific and Philippine Sea plates — which are slowly grinding against each other, building up enormous seismic pressure.
The government’s Earthquake Research Committee has warned of a 70 percent chance that a great, magnitude-eight quake will strike within the next 30 years in the Kanto plains, home to Tokyo’s vast urban sprawl.
In 1995 Kobe earthquake killed more then 6,400 people.
More than 220,000 people were killed when a 9.1-magnitude quake hit off Indonesia in 2004, unleashing a massive tsunami that devastated coastlines in countries around the Indian Ocean as far away as Africa.
Small quakes are felt every day somewhere in Japan and people take part in regular drills at schools and workplaces to prepare for a calamity.
Nuclear power plants and bullet trains are designed to automatically shut down when the earth rumbles and many buildings have been quake-proofed with steel and ferro-concrete at great cost in recent decades.
Meanwhile, at least eight people were reported killed after a huge earthquake of magnitude 8.9 rocked Japan and tsunamis up to 10 metres (33 feet) high slammed into the Pacific coast today.
The dead included a 67-year-old man crushed by a wall and an elderly woman killed by a fallen roof, both in the wider Tokyo area, press reports said.
Three were crushed to death when their houses collapsed in Ibaraki prefecture Northeast of Tokyo. - AFP
(Editor's Note: To contact the control centre at the Malaysian Embassy in Japan, call 008 133 476 3840)
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