The largest earthquake in Japan's recorded history struck offshore Friday, leaving officials scrambling to restore services, put out fires and search for survivors after an ensuing tsunami washed away homes, roads, cars and ships.

Police said Friday they've found between 200 and 300 bodies in the coastal city of Sendai, with 236 confirmed dead elsewhere. More than 750 people are missing, with the toll expected to rise. More than a 1,000 people were also reported injured.

Officials said it could be a while before rescuers are able to reach the most-damaged area because of sludge and debris, making a precise body count difficult to attain.

The death toll is expected to exceed 1,000.

At first sunlight Saturday, the extent of the devastation was becoming heartbreakingly clear.

Thousands of homes have been destroyed, many roads are impassable and power and cell phone service is out in the affected area.

The quake sparked at least 80 fires.

Much of the city of Kesennuma, home to 74,000 people, burned overnight. The city was near the quake's epicenter.

Local broadcasters said one-third of the city was underwater, while the rest was burning.

More than 300 houses were washed away in Ofunato City, and a large fire erupted at the Cosmo oil refinery in Ichihara city in Chiba prefecture.

Near Ofunato, there was a large "SOS" spelled out in English at one school.

In the coastal town of Minami-soma, nearly 2,000 houses were destroyed or severely damaged, the Defence Ministry said.

Chief Cabinet Secretary Yukio Edano said the country's initial assessment found "enormous damage" and the Defence Ministry was sending troops to the hardest hit areas.

Strongest recorded quake in Japan

The earthquake struck at 2:46 p.m. local time on Friday afternoon, at a depth of 24 kilometres about 125 kilometres off the eastern coast, and was followed by at least 50 powerful aftershocks.

Japan's meteorological agency said the initial earthquake registered at a magnitude of 8.8, while the U.S. Geological Survey said it measured a magnitude 8.9 -- enough to rank it fifth among all quakes registered in the past 111 years.

Most of the aftershocks registered at 6.0, with one reaching 7.1. Japan's Meteorological Agency also said a separate 6.4 magnitude earthquake struck central Japan early Saturday morning, shaking buildings in Tokyo.

By comparison, the recent quake that claimed more than 160 lives in New Zealand was measured at 6.3, about 8,000 times less powerful.

Christian Cote, a Canadian working in Fukushima, about an hour southwest of Sendai, said the aftershocks were strongest in the hours immediately following the afternoon quake.

"Since then -- this was more than 12 hours ago -- we've been experiencing repeated aftershocks," Cote told CTV News Channel by telephone.

Prime Minister Naoto Kan has appeared on television, urging all Japanese to remain calm.

"The earthquake has caused major damage in broad areas in northern Japan," Kan said, asking people along Japan's 2,100-kilometre east coast to move to higher ground in advance of more devastating waves.

Several waves, including one estimated at seven metres high, sent crushing walls of water littered with boats and buildings over cities and coastal farmland as well as the airport near the region's largest city, Sendai.

Japan's public broadcaster NHK reports that fires, likely triggered by gas pipes ruptured in the crush of tons of debris-packed water, are spreading throughout sections of the city.

Dozens of fires were also reported across the northern prefectures of Fukushima, Iwate and Ibaraki. Collapsed homes and landslides were also reported in Miyagi, of which the million-strong city of Sendai is the capital.

But authorities were still trying to determine the full scale of the quake's impact.

"We don't even know the extent of damage," said Hiroshi Sato, a disaster management official in the northern prefecture of Iwate. "Roads were badly damaged and cut off as tsunami washed away debris, cars and many other things."

Tsunami alerts were issued all along the Pacific, although the waves that hit the U.S. and Canada were not as bad as feared.

Evacuation ordered

Officials have declared states of emergency at two different nuclear power plants and ordered evacuations.

Journalist Chris Johnson said the quake's enormity was evident, even in the capital area where NHK reported that 4 million buildings were without power.

"It felt like the big one that everyone's been expecting here in Tokyo. But, in fact, it was more than 300 kilometres away," Johnson told CTV in a telephone interview from Tokyo.

Although initial reports suggest no major damage in Tokyo, the train and subway service that typically carries more than 10 million travellers every day has been halted, stranding countless rush hour commuters. Service has also been halted indefinitely at the city's Narita airport.

'Ring of Fire'

Several quakes had hit the same northeast region of Japan in recent days, including a 7.3-magnitude tremor on Wednesday.

Because it is situated in the earthquake and volcano-prone region of the Pacific known as the "Ring of Fire", Japan is among the countries best prepared for such devastating events.

Even so, Osama Akiya told the AP that this one was exceptional.

"I've been through many earthquakes, but I've never felt anything like this," Akiya said, describing his experience as the quake shook his downtown Tokyo office.

Japan's worst earthquake claimed 143,000 lives when it struck Kanto in 1923. The magnitude 7.2 temblor that devastated Kobe in 1996 killed 6,400 people.

  • Friday's quake, which struck near the east coast of Honshu, Japan, shook the earth for more than 2 minutes
  • According to the U.S. Geological Service, the temblor was caused by "thrust faulting on or near the subduction zone interface plate boundary between the Pacific and North America plates"
  • The quake triggered tsunami warnings in at least 80 locations worldwide, from Alaska to Kenya to Indonesia
  • Each year, approximately one-in-five of the world's earthquakes measuring magnitude 6 or greater occurs in Japan
  • The Tokyo-Yokohoma metropolitan area, which is home to some 35 million people, topped the list of the world's most "at risk" cities in a 2004 German insurer's report on the threat of natural disasters
  • Japan has enacted a series of earthquake preparedness laws that lay out strict guidelines for evacuation routes, strengthening building structures and shoring coastal embankments against tsunamis

With files from The Associated Press