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.
A tsunami warning was extended across the Pacific to New Zealand in the south and North and South America to the east.
The Red Cross in Geneva warned that the tsunami waves could be higher than some Pacific islands, Reuters news agency said.
Coastal areas in the Philippines, Hawaii and other Pacific islands were evacuated ahead of the tsunami's expected arrival.
Wall of water Strong waves hit Japan's Miyagi and Fukushima prefectures, officials said, damaging dozens of coastal communities. Kyodo news agency said a 10-metre wave (33ft) struck the port of Sendai in Miyagi prefecture.
Japan's NHK television showed a massive surge of debris-filled water sweeping away buildings, cars and ships and reaching far inland.
Motorists could be seen trying to speed away from the wall of water.
Farmland around Sendai was submerged and the waves pushed cars across the runway of the city's airport. Fires broke out in the city's centre.
Another fire was reported to be burning in the turbine building of the Onagawa nuclear plant in Miyagi prefecture.
The UN's nuclear agency said four nuclear power plants had shut down safely. Prime Minister Naoto Kan said there had been no radiation leaks.
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.
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.
'Seasick' The earthquake also triggered a massive blaze at an oil refinery in Ichihara city in Chiba prefecture near Tokyo, engulfing storage tanks.
There were reports of about 20 people injured in Tokyo after the roof of a hall collapsed on to a graduation ceremony.
Residents and workers in Tokyo rushed out of apartment buildings and office blocks and gathered in parks and open spaces as aftershocks continued to hit.
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.
About four million homes in Tokyo suffered power outages.
In a televised address, Prime Minister Naoto Kan extended his sympathy to the victims of the disaster and said an emergency response headquarters had been set up.
