Breaking News: Powerful quake triggers tsunami in Japan

 An 8.9-magnitude earthquake struck off Japan's northeastern coast on Friday, triggering a 20-foot tsunami that washed away vehicles, boats and buildings. The massive quake, which struck at 2:46 p.m., was followed by a series of powerful aftershocks, one measuring 7.4 on the Richter scale.

Houses are washed away by tsunami in Sendai, eastern Japan Photograph

NHK Japan, the country's national television, broadcast footage of boats, cars and trucks, and farms and buildings being swept away along the northern Pacific coast. The wall of water moving inland can be seen swamping everything in its path.

Vehicles are washed away by tsunami in coastal area in eastern Japan Photograph

The Pacific Tsunami Warning Center issued evacuation alerts for the entire Pacific coast of Japan, as well as Russia, Marcus Island and the northern Mariani islands.

A tsunami watch was also issued for Guam, Taiwan, the Philippines, Indonesia and Hawaii.

In Tokyo, workers poured out into the streets from high-rise buildings that shook and swayed precariously.

An office building burns in Tokyo after an earthquake Friday

"The building shook for what seemed like a long time and many people in the newsroom grabbed their helmets and some got under their desks," Reuters' correspondent Linda Sieg said.

People stand outdoors after evacuating from nearby buildings in Tokyo's financial district.

"It was probably the worst I have felt since I came to Japan more than 20 years ago," she said.

A roof collapsed in a building in Tokyo where a graduation ceremony for 600 students was being held, injuring an unknown number of people.

Rescue workers help people on the streets of Tokyo's financial district after an earthquake off the coast of northern Japan Friday. The quake reportedly caused many injuries, fires and a four-metre tsunami along parts of the country's coastline. There were several strong aftershocks and a warning of a larger tsunami following the quake, which caused buildings to shake violently in the capital. 

An oil refinery in Chiba prefecture is battling a major fire. Tokyo's airports were shut down as was Tokyo Metro and the bullet trains.

Reuters has a useful summary of events:

• At least two people reported dead, one hit by a collapsing wall at a Honda factory. Several people buried in landslide.

• Quake triggers tsunami up to 10 metres (30 feet), waves sweep across farmland, sweeping away homes, crops, vehicles, triggering fires. Tsunami of 7 metres later hits northern Japan. Inn collapses in Sendai city, many are feared buried in rubble.

• Strong aftershocks hit northern Japan.

• Tsunami warnings issued for eastern Indonesia, Taiwan's north and east coasts.

• Power cut to four million homes in and around Tokyo. Fourteen fires blaze in Tokyo.

• Many sections of Tohoku expressway serving northern Japan damaged. Major fire at Chiba refinery near Tokyo.

• Bullet trains to the north of the country stopped.

• The government was to dispatch 900 rescue workers to stricken regions.

• Narita airport closed, flights halted, passengers evacuated. Tokyo underground, suburban trains halted. Sendai airport in the north flooded.

• Eight military planes scrambled to survey damage. Prime Minister Naoto Kan asks people to remain calm and orders the military to do their utmost to act. Cabinet to meet.

• The government says more tsunami possible.

• Central bank vows to do utmost to ensure financial market stability

• Several nuclear power plants shut down automatically. Tepco's Fukushimi No. 1 plant had an equipment problem after the quake, but safety is ensured, officials say. At least one nuclear power station operating normally. Oil refineries have shut down and a major steel plant was ablaze.

8.04am: More from Japanese prime minister Kan. He extended his "deepest sympathies" to the victims of the earthquake. He also offered some reassurance about Japan's nuclear facilities. He said:

Some of the nuclear power plants have stopped automatically but so far no radioactive material has been confirmed to have been leaked to the outside.

Authorities shut all 19 water gates at Tokyo's port, and more than four million buildings in Tokyo and its suburbs lost power, NHK reported.

The quake's epicenter struck about 80 miles off Japan's east coast - about 240 miles from Tokyo - at a depth of six miles, according to the U.S. Geological Survey.

On Wednesday, a 7.2-magnitude quake that struck off Honshu could be felt in Tokyo. A tsunami warning was issued, but waves stayed under two feet.

In 1933, an 8.1-magnitude earthquake killed 3,000 people in Japan.