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, and numerous casualties are feared.
It struck about 250 miles (400km) from the capital at a depth of 20 miles. There have been powerful aftershocks.
The tremor hit at 1446 local time (0546 GMT). Seismologists say it is one of the largest earthquakes to hit Japan for many years.
The tsunami warning was extended to the Philippines, Indonesia, Taiwan, the Pacific coast of Russia and Hawaii.The Pacific Tsunami Warning Center said the wave could extend as far as Chile.
Tsunami waves hit Japan's Miyagi and Fukushima prefectures, officials said, damaging dozens of coastal communities.
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 the coastal city of Sendai was submerged and the waves pushed cars across the runway of the city's airport.
'Seasick' The earthquake also triggered a number of fires, including one 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, rapid transit in Tokyo was suspended and some nuclear power plants automatically shut down.
Prime Minister Naoto Kan said there had been no radiation leaks.
In a televised address, he extended his sympathy to the victims of the disaster and said an emergency response headquarters had been set up.
He said the earthquake had a magnitude of 8.4 while the US Geological Survey said it measured 8.9.