Japanese Prime Minister Naoto Kan on Sunday said the country was facing its worst crisis since World War II, as the toll from the earthquake and tsunami two days ago is expected to cross 10,000 and fears arose of a nuclear fallout from two quake-hit reactors.
Kan said the situation at the Fukushima nuclear plant "continues to be in an alarming state", DPA quoted the Kyodo news agency as saying.
Radiation levels had surpassed the legal limits at the Fukushima I plant in northeastern Japan, 240 km north of Tokyo, officials said, raising concerns over radiation leaks and a possible core meltdown.
According to DPA, nuclear reactors at the Fukushima I and II plants lost their cooling functions after power and backup generators were cut off due after the quake.
Some 200,000 people have been evacuated from a 20-km safety zone around the two plants. At least 19 people have been exposed to radioactivity, Kyodo said.
Following the quake, about 390,000 people have fled their homes, many of them finding a place to stay at the more than 1,400 emergency shelters set up in schools and community centres, public broadcaster NHK said.
Prime Minister Kan told reporters that more than 12,000 people had been rescued since Friday. But as local and international search-and-rescue teams continued their search for survivors, police said more than 1,000 bodies had been found.
He said that more than 600,000 people in the worst-hit areas had taken refuge in schools and community centres.
Kan doubled the number of soldiers sent to the affected region to 100,000 as rescue workers were struggling to reach quake-hit areas with many roads blocked by debris.
"I ask for utmost efforts to save the lives of as many people as possible," Kyodo quoted Kan as saying after a meeting of the government's emergency disaster headquarters. "We will put all-out efforts into rescuing people who have been isolated."
Drinking water was transported to quake-hit regions by truck, and witnesses said residents were rushing to stock up on supplies at supermarkets and petrol stations, buying food and heating oil.
Railway links to the quake-hit regions are to remain closed, Japan Rail said, but it resumed operations in the Tokyo metropolitan area. Highways were also closed.
While the official figures put the death at over 1,000, many felt the real picture was more and alarming.
Takeuchi Naoto, the police chief of the hardest-hit prefecture of Miyagi, said he had "no doubt" the toll would rise above 10,000 in the prefecture alone, NHK said.
Meanwhile, an unbelievable calm was witnessed in Miyagi as residents despite being hit with shortage of drinking water and meal showed no panic.
"The shop has all its windows and its glass door broken. There is an ATM and shelves with food products inside the shop and no one is guarding it. However, not a person has ever entered it and nothing has been looted," an eyewitnesses said.
"Gas and water have been switched off in Miyagi and the central city of Sendai. With rare exceptions, electricity is also off. But there is no panic either in the streets or shops," the eyewitness, who arrived in Miyagi several hours after Friday's earthquake, said.
The earthquake, considered the fifth most powerful in the recorded history, triggered a huge tsunami that washed away everthing in its way -- cars, ships, planes, house and farmlands.
"In some places, we saw that houses and buildings had been completely destroyed," Mikiko Dotsu, the coordinator of a team from Medecins Sans Frontieres, said after she arrived in Sendai near the quake's epicentre.
She said 90 disaster medical assistance teams were deployed in Miyagi.
"At the moment, there is very little electricity and no water supply," Dotsu said. "People need food, blankets and water. These needs are bigger than medical needs at the moment."
Miyagi and Fukushima prefectures saw some of the worst destruction.
A municipal official in Futaba town in Fukushima prefecture told Kyodo news that about 90 percent of the houses in three coastal communities had been washed away by the tsunami.
Even two days after the devastation, Japan reeled under powerful aftershocks.
An earthquake measuring 6 on the Richter scale struck off the east coast of Honshu in Japan, Sunday, according to the China Earthquake Network Center.
The epicenter, with a depth of 20 km, was monitored at 37.3 degrees north latitude and 142.6 degrees east longitude.