From BBC news:
A massive earthquake has hit the north-east of Japan, triggering a tsunami that has caused extensive damage. Japanese television showed cars, ships and even buildings being swept away by a vast wall of water after the 8.9-magnitude earthquake.
The quake has sparked fires in several areas including Tokyo. At least 32 people were killed, officials said. It struck about 250 miles (400km) from the capital at a depth of 20 miles. There have been powerful aftershocks.
The tremor, measured at 8.9 by the US Geological Survey, hit at 1446 local time (0546 GMT). Seismologists say it is one of the largest earthquakes to hit Japan for many years.
Police and local officials said at least 32 people had been killed in the earthquake and tsunami. It is believed the death toll could rise significantly.
A ship carrying 100 people was swept away, Japanese media reported, quoting police in Miyagi. It is not clear what happened to the ship and its passengers.
In Iwate prefecture, also near the epicentre, an official said it was difficult to gauge the extent of the destruction.
"Roads were badly damaged and cut off as the tsunami washed away debris, cars and many other things," said Hiroshi Sato, a disaster management official in Iwate.
Many people in Tokyo said they had never felt such a powerful earthquake.
In central Tokyo, Jeffrey Balanag said he was stuck in his office in the Shiodome Sumitomo building because the elevators had stopped working.
"There's no panic but we're almost seasick from the constant rolling of the building," he told the BBC.
Bullet train services to northern Japan were halted and rapid transit in Tokyo was suspended, stranding many workers in the city centre. Narita airport outside Tokyo was initially closed but later opened for departing flights.
About four million homes in and around Tokyo suffered power outages...
I'm trying to find out more information on how people can help but in meantime, here are some useful links:
Sky News: Lots of information and pictures here
2011 Japan Earthquake info & person finder (powered by Google)
Donate to British Red Cross
Vocabulary: earthquake - tremblement de terre/séisme
tsunami - tsunami
Updated: 15 March
A whole bunch of ways you can help/donate