Large fishing boats and other vessels rode high waves ashore, slamming against overpasses or scraping under them and snapping power lines along the way. Upturned and partially submerged cars bobbed in the water. Ships anchored in ports crashed against each other.
A Japanese coast guard official says a search is under way for a ship carrying 80 dock workers that was swept away. The vessel was washed away from a shipbuilding site in Miyagi prefecture, the most affected area.
The tsunami roared over embankments, washing anything in its path inland before reversing directions and carrying the cars, homes and other debris out to sea. Flames shot from some of the homes, probably because of burst gas pipes.
Waves of muddy waters flowed over farmland near Sendai, carrying buildings, some of them ablaze. Drivers attempted to flee. Sendai airport was inundated with thick, muddy debris that included cars, trucks, buses and even light planes.
“The earthquake has caused major damage in broad areas in northern Japan,” Prime Minister Naoto Kan said at a news conference.
Highways to the worst-hit coastal areas buckled. Telephone lines snapped. Train service in northeastern Japan and in Tokyo, which normally serve 10 million people a day, were suspended, leaving untold numbers stranded in stations or roaming the streets. Tokyo's Narita airport was closed indefinitely.
“Our initial assessment indicates that there has already been enormous damage,” chief government spokesman Yukio Edano said. “We will make maximum relief effort based on that assessment.”
He said the Defence Ministry was sending troops to the quake-hit region. A utility aircraft and several helicopters were on the way.
More than 45 countries were awaiting a request from Tokyo after offering to help, the United Nations said on Friday.
Some 68 search and rescue teams from 45 countries were on standby, but the United Nations was awaiting a green light from authorities in Japan to deploy, said Elisabeth Byrs of the U.N. Office for the Coordination of Humanitarian Affairs (OCHA).
U.S. President Barack Obama spoke to Japanese Prime Minister Naoto Kan to offer to help “in any way possible“, the Japanese Jiji agency reported.
The Defense Department was preparing American forces in the Pacific Ocean to provide relief after the quake.
The Russian emergency services agency ERMACOM offered 40 people with three sniffer dogs, while Singapore had civil defence forces on standby and Poland offered firefighters.
China, Switzerland and the United States also offered rescue teams, while Britain, France and others said they were ready to offer whatever help was required.
A large fire erupted at the Cosmo oil refinery in Ichihara city in Chiba prefecture near Tokyo and was burning out of control with 30-metre-high flames whipping into the sky.
Also from Miyagi prefecture, NHK showed footage of a large ship being swept away and ramming directly into a breakwater in Kesennuma city.
The U.S. Geological Survey said the 2:46 p.m. quake was a magnitude 8.9, the biggest earthquake to hit Japan since officials began keeping records in the late 1800s.
A tsunami warning was extended to a number of Pacific, Southeast Asian and Latin American nations, including Japan, Russia, Indonesia, New Zealand and Chile. In the Philippines, authorities said they expect a metre high tsunami.
Waves from the tsunami hit Hawaii close to 8 a.m. ET, the Pacific Tsunami Warning Center says Kauai was the first island hit early Friday by the tsunami, which was quickly sweeping through the Hawaiian Island chain. Officials predicted Hawaii would experience waves up to 6 feet.
Residents in coastal areas of Hawaii were evacuated to refuge areas at community centers and schools while tourists in Waikiki were moved to higher floors of their high-rise hotels.
The National Oceanic and Atmospheric Administration gives estimated arrival times for the tsunami along the North American Pacific Coast, the first contact with the north tip of Vancouver Island is expected at 6:26 PST.
The quake struck at a depth of 10 kilometres, about 125 kilometres off the eastern coast, the agency said. The area is 380 kilometres northeast of Tokyo.
The quake brought super-modern Tokyo to a standstill Friday, paralyzing trains that normally run like clockwork and stranding hordes of commuters carrying mobile phones rendered largely useless by widespread outages.
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