A devastating tsunami is engulfing towns in Japan's northern Pacific coast following a major offshore quake today. Japanese television is broadcasting cars, ships and even buildings being swept away by a vast wall of water.

Towns and farms around Sendai city in northern Japan are being swallowed, and a four-metre wave has engulfed parts of Kamaishi on the Pacific coast.
Officials said the wave could be 10m (33ft), and numerous casualties are feared.

Before the tsunami, a massive 8.8 magnitude quake hit the northeast coast of Japan, shaking buildings in the capital Tokyo, causing "many injuries", at least one fire and triggering a four-metre (13-ft) tsunami, NHK television and witnesses reported.

The public broadcaster showed flames and black smoke billowing from a building in Odaiba, a Tokyo suburb, and bullet trains to the north of the country were halted. Black smoke was also pouring out of an industrial area in Yokohama's Isogo area.

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

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

Passengers on a subway line in Tokyo screamed and grabbed other passengers' hands. The shaking was so bad it was hard to stand, said Reuters reporter Mariko Katsumura.

Following the earthquake, the meteorological agency issued its top-level evacuation alerts for the entire Japanese coast. The agency said 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. It also put Guam, Taiwan, the Philippines, the Marshall Islands, Indonesia, Papua New Guinea, Nauru, Micronesia and Hawaii under a lower tsunami watch.

The Joint Australian Tsunami Warning Centre says there is no tsunami threat to Australia, although the US tsunami monitoring centre has widened a warning to virtually the entire Pacific coast, including Australia and South America.

The Tokyo stock market extended its losses after the quake was announced. The central bank said it would do everything to ensure financial stability.

With Reuters