2000 bodies washed up as Japan shaken by new tsunami scare and reactor blast

About 2000 bodies have reportedly been found on the shores of Miyagi prefecture.

The grim development, reported by Kyodo news agency, comes as Japan's weather agency said there was no current risk of another deadly wave hitting Japan's north-eastern coast, following earlier TV reports of a three-metre wave heading for the coast.

About 1000 people were found washed up on the shores of Ojika Peninsulain Miyagi, while another 1000 were seen in the town of Minamisanriku, the agency said, adding that in Minamisanriku authorities have been unable to contact 10,000 people – more than half of the population living there.

Officials were hopeful about unconfirmed reports that many of the town's residents were uncontactable because they had evacuated to nearby Tome city, Kyodo reported.

A Japan Meteorological Agency official said in a live broadcast shown on public broadcaster NHK, following reports that the three-metre high wave was spotted from a fire department helicopter off Fukushima prefecture, that any wave was unlikely to be higher than several tens of centimetres.

The sea was reportedly seen retreating off Iwate prefecture in the north-east of Honshu island, a phenomenon that occurs before the massive waves hit, and residents were being ordered to higher ground.

Earlier today a 5.8 magnitude  quake - one of many aftershocks since Friday's massive 9 quake - struck at a depth of 18 kilometres off Ibaraki prefecture, shaking tall buildings in Japan's capital.

New explosion at nuclear plant

Japan has been battling to control two overheating reactors at the ageing Fukushima plant after the cooling systems were knocked out by Friday's quake.

Shortly after Prime Minister Naoto Kan said the plant was still in an "alarming" state, a blast at its number-three reactor shook the facility and sent plumes of smoke billowing into the sky.

The plant's operator TEPCO said that nine people were injured in the blast, which authorities said was probably a hydrogen explosion.

The chief government spokesman Yukio Edano said TEPCO reported that the reactor was probably undamaged and there was a low possibility of a major radiation leak at the plant, 250 kilometres northeast of Tokyo.

Another explosion blew apart the building surrounding the plant's number-one reactor on Saturday but the seal around the reactor itself remained intact.

Noriyuki Shikata, the Japanese Deputy Cabinet Secretary for Public Relations, added that the blast at No.3 was "deemed to be the same" type of explosion that occurred at the No.1 reactor on Saturday.

Reactor No.3 "remains healthy" and there was no recorded increase in the radiation around the plant, he said.

Operators had earlier halted injection of seawater into the reactor, resulting in a rise in radiation levels and pressure.

The government had warned that an explosion was possible because of the build-up of hydrogen in the building housing the reactor.

The International Atomic Energy Agency (IAEA) said Japanese authorities reported that radioactivity levels "at the site boundary" of another nuclear power plant at Onagawa had returned to normal.

A mass evacuation of about 210,000 tsunami survivors from near the Fukushima nuclear power complex was still under way last night.

US sailors expopsed to radioactivity

The effects of the radioactive plumes from the problematic nuclear reactors have spread further afield, with US government officials telling reporters crew members on the deck of USS Ronald Reagan were exposed to about a month's worth of radiation in one hour when the nuclear-powered aircraft carrier sailed through the Pacific.

''The maximum potential radiation dose received by any ship's force personnel aboard the ship when it passed through the area was less than the radiation exposure received from about one month of exposure to natural background radiation from sources such as rocks, soil, and the sun,'' the spokesman for the Seventh Fleet, Commander Jeff Davis, told ABC News.

US military helicopters flying 60 miles (96.5 kilometres) north of the reactors were also covered by particulate radiation from the radioactive cloud, officials told the Times.

The newspaper reported that none of the crew became ill from the exposure.

''The low level radioactivity was easily removed from affected personnel by washing with soap and water. They were subsequently surveyed, and no further contamination was detected,'' Commander Davis said of the 17 crew members aboard the helicopters.

USS Ronald Reagan and six other ships, which were moved to the eastern coast of Japan to take part in relief operations, have been repositioned downwind from the plants, Commander Davis added.

1000 bodies recovered

Authorities said about 1000 bodies were recovered yesterday from the mud-streaked wreckage along the coast north of Tokyo, but the death toll from Friday's tsunami in the worst hit Miyagi prefecture would rise beyond 10,000, police said. About 2.5 million homes were without power and 1.4 million without water.

A total of 380,000 people have been evacuated to shelters after more than 20,000 buildings were wiped out along the coastline.

The Department of Foreign Affairs and Trade (DFAT) said 1973 Australians, including 102 in the affected areas, were confirmed safe as of 5.30am today.

There are 2948 Australians registered in Japan, with 234 registered in the areas devastated by the earthquake and tsunami.

Those confirmed safe include registered and unregistered Australians, a DFAT spokesman said.

A total of 6797 calls have been received by the Consular Emergency Centre since Friday.

Australia's ambassador to Japan Murray McLean said it was difficult to know exactly how many Australians were affected by the earthquake.

"We really, honestly, do not know how many Australians were in Japan on the day of the big earthquake," he told the ABC.

"The numbers are fluctuating."

Foreign Affairs Minister Kevin Rudd said DFAT had no further information about 25-year-old Melbourne man Jason Briffa, whose mother was concerned he had not been in contact since Friday afternoon before the quake.

But he said DFAT officials were working with the Japanese to find Mr Briffa, who was working as an English teacher in Sendai.

"We will not spare any effort in tracking down the whereabouts of each and every Australian that we haven't been able to identify so far," Mr Rudd told the Nine Network this morning.

Huge aftershocks continued to rumble through the region yesterday, and tsunami warnings were still current along many sections of the coast.

Hundreds exposed to radiation

About 160 people had been exposed to dangerous radiation levels close to the power stations, the Japanese Nuclear and Industrial Safety Agency said, with at least three plant workers showing severe symptoms of radiation sickness. One power station worker was killed while operating a crane at the site, and eight others have been injured.

Japanese public television broadcast nuclear emergency warnings, telling people who were still close to the plants to stay indoors, not to drink water, to cover exposed skin and to place wet towels over their mouths and noses to ward off contamination. Some people had been issued with iodine pills to counteract radiation sickness.

Australia's nuclear safety agency, ARPANSA, said there was no immediate risk outside a 20-kilometre exclusion zone around the plants.

Australian nuclear specialists told the Herald there were grounds for believing the Japanese authorities could bring the emergency under control if enough water could be pumped through into the reactors to keep the uranium fuel rods cool for the next few days.

A complete meltdown - the collapse of a power plant's ability to keep temperatures under control - could release uranium and dangerous contaminants into the environment and pose major, widespread health risks.

Experts noted, however, that even a complete meltdown would probably be far less severe than the 1986 disaster at Chernobyl, where a reactor exploded and sent a cloud of radiation over much of Europe. That reactor, unlike the ones in Fukushima, was not housed in a sealed container.

Significant build-up of radiation is unlikely

Ziggy Switkowski, who was chairman of the Australian Nuclear Science and Technology Organisation [ANSTO] until a few months ago, said a significant build-up of radiation was unlikely.

"The contribution, if any, to this [disaster] from the nuclear fleet, I expect even under worst case scenarios is going to be small," he told Fairfax Radio Network this morning.

"That's not to deny that people are always concerned and justly concerned about the integrity of the nuclear reactor network," Dr Switkowski said.

"The Japanese reactors are probably as good as you can find around the world, but this magnitude 9 earthquake may well have tested the limits of their design."

Japan has 55 reactors spread across 17 complexes nationwide.

100,000 soldiers involved in relief efforts

The wider relief effort included 100,000 soldiers, who have concentrated in the crescent of coast north of Tokyo, including the Miyagi and Chiba prefectures.

In Iwaki, residents were leaving due to concerns over supplies. The town had no electricity and all shops were closed. Police had taken in about 90 people and given them blankets and rice balls but there was no sign of aid trucks.

The earthquake itself was upgraded to magnitude 9 by Japanese seismologists - making it the biggest to hit that region.

"Our country faces its worst crisis since the end of the war 65 years ago," the Prime Minister, Naoto Kan, said yesterday. "I'm convinced that working together with all our might the Japanese people can overcome this."

Losses of nearly $US34.5 billion feared

The devastating earthquake could lead to insured losses of nearly $US35 billion, risk modelling company AIR Worldwide said, making it one of the most expensive catastrophes in history - even without expected additional tsunami losses that are not yet counted.

AIR said its loss estimate range was $US14.5 billion to $US34.6 billion. That was based on a range of 1.2 trillion yen to 2.8 trillion yen, converted at 81.85 yen to the US dollar.

The company cautioned that the estimate was preliminary, and its models do not factor in the effects of the tsunami that followed the earthquake, or any potential losses from nuclear damage.

- with agencies

Australians concerned about their family and friends in Japan can phone DFAT's 24-hour Consular Emergency Centre on 1300 555 135.

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