Japan's nuclear crisis escalated today, with two more blasts and a fire rocking a quake-stricken atomic power plant, sending radiation up to dangerous levels.

Radiation around the Fukushima No 1 plant on the eastern coast had "risen considerably", Prime Minister Naoto Kan said, and his chief spokesman announced the level was now high enough to endanger human health.

In Tokyo, some 250km to the southwest, authorities also said that higher than normal radiation levels had been detected in the capital, the world's biggest urban area, but not at harmful levels.

azlanHowever, city officials said that the level of radiation in Tokyo has fallen at 5pm (4pm Malaysian time).

Kan had earlier warned people living within 30km of  the nuclear plant to stay indoors.

The fire, which was later extinguished with the help from US troops, was burning in the plant's No 4 reactor, he said, meaning that four out of six reactors at the facility are now in trouble.

Kan also strongly criticised the operator the power plant.

"The TV reported an explosion. But nothing was said to the premier's office for about an hour," the Kyodo News quoted him as saying.

"What the hell is going on?" he asked in frustration.

The crisis at the aging Fukushima plant has escalated daily after last Friday's quake and tsunami, which knocked out its cooling systems.

On Saturday, an explosion blew apart the building surrounding the plant's No 1 reactor. Yesterday, a blast hit the No 3 reactor, injuring 11 people and sending plumes of smoke billowing into the sky.

Radioactive substances leaked 

Authorities are trying to prevent meltdowns in all three of the plant's nuclear reactors by flooding the chambers with sea water to cool them down.

Early today a blast hit the No 2 reactor. That was followed shortly after by a hydrogen explosion which started a fire at the No 4 reactor.

Chief government spokesman Yukio Edano said radioactive substances were leaked along with the hydrogen.

japan tsunami earthquake radiation check nuclear power plant explosion 1"What we most fear is a radiation leak from the nuclear plant," Kaoru Hashimoto, 36, a housewife living in Fukushima city, 80km northwest of the stricken plant, told AFP by phone.

"Not much confirmed information is coming to us, so we are in trouble about how to cope with the situation."

Hashimoto said supermarkets were open, but the shelves were completely empty.

"Many children are sick in this cold weather but pharmacies are closed. Emergency relief goods have not reached evacuation centres in the city," she said.  

azlanThe full extent of the destruction wreaked by last Friday's massive quake and the tsunami that followed are still becoming clear, as rescuers combed through the region north of Tokyo where officials say at least 10,000 people were killed.

"It's a scene from hell, absolutely nightmarish," said Patrick Fuller of the International Red Cross Federation from the northeastern coastal town of Otsuchi.

Prime Minister Naoto Kan has said Japan was facing its worst crisis since World War II and, with the financial costs estimated at up to US$180 billion, analysts said it could tip the world's third-biggest economy back into recession.

The US Geological Survey upgraded the quake to magnitude 9.0 on the Richter Scale, from 8.9, making it the world's fourth most powerful since 1900.

Car makers, shipbuilders and technology companies worldwide scrambled for supplies after the disaster shut factories in Japan and disrupted the global manufacturing chain.
          
‘Not Chernobyl’

The fear at the Fukushima complex, 240km north of Tokyo, is of a major radiation leak after the quake and tsunami knocked out cooling systems. The complex had already seen explosions at its No 1 and No 3 reactors.

japan nuclear fukushima no 3 reactor explosion imageJiji news agency said today's early morning explosion had damaged the roof and steam was rising from the complex.

It also reported many workers had been told to leave the plant, a development one expert had warned beforehand could signal a worsening stage for the crisis.

Tepco said it has pulled out 750 workers from the plant since Tuesday, and only 50 remain.

The worst nuclear accident since the Chernobyl disaster in Ukraine in 1986 has drawn criticism that authorities were ill-prepared and revived debate in many countries about the afety of atomic power.

Switzerland put on hold some approvals for nuclear power plants and Germany said it was scrapping a plan to extend the life of its nuclear power stations. The White House said US President Barack Obama remained committed to nuclear energy.

Yukiya Amano, head of the International Atomic Energy Agency, said the reactor vessels of nuclear power plants affected by the disaster remained intact.

Chernobyl-style disaster 'very unlikely'

"The nuclear plants have been shaken, flooded and cut off from electricity," he told a news conference. But "the reactor vessels have held and radioactive release is limited."

Amano, a veteran Japanese diplomatic, added that a Chernobyl-style disaster was "very unlikely".

An explosion at the Soviet Chernobyl plant sent radioactive fallout across northern Europe.

While the Fukuskima plant's No 1 and No 3 reactors both suffered partial fuel rod meltdowns, operator Tokyo Electric Power Co (Tepco) had earlier said the No 2 reactor was now the biggest concern.

A sudden drop in cooling water levels when a pump ran out of fuel had fully exposed the fuel rods for a time, an official said. This could lead to the rods melting down and a possible radioactive leak.

Tepco had resumed pumping sea water into the reactor early on Tuesday.

"This is nothing like a Chernobyl," said Murray Jennex, a nuclear expert at San Diego State University. "At Chernobyl you had no containment structure - when it blew, it blew everything straight out into the atmosphere."

Nonetheless, the Japanese government warned those still in the 20km evacuation zone to stay indoors. Tepco said 11 people had been injured in the blast.

NONEUS warships and planes helping with relief efforts moved away from the coast temporarily because of low-level radiation.

The US Seventh Fleet described the move as precautionary.

South Korea, Hong Kong, Singapore and the Philippines said they would test Japanese food imports for radiation.

France's ASN nuclear safety authority said the accident was classified as a level 6 on the international scale of 1 to 7, putting it worse than the 1979 US Three Mile Island meltdown, higher than the Japanese authorities' rating.

Japan's nuclear safety agency has rated the incidents in the No 1 and No 3 reactors as a 4, but has not yet rated the No 2 reactor.

The 1986 Chernobyl disaster was a 7 on the scale.

Towns flattened


About 850,000 households in the north were still without electricity in near-freezing weather, Tohuku Electric Power Co said, and the government said at least 1.5 million households lack running water. Tens of thousands of people were missing.

"The situation here is just beyond belief, almost everything has been flattened," said the Red Cross's Fuller in Otsuchi, a town all-but obliterated. "The government is saying that 9,500 people, more than half of the population, could have died and I do fear the worst."

NONEKyodo news agency reported that 2,000 bodies had been found on Monday in two coastal towns alone.

Whole villages and towns have been wiped off the map by last Friday's wall of water, triggering an international humanitarian effort of epic proportions.

"When the tsunami struck, I was trying to evacuate people. I looked back, and then it was like the computer graphics scene I've seen from the movie Armageddon. I thought it was a dream. It was really like the end of the world," said Tsutomu Sato, 46, in Rikuzantakata, a town on the northeast coast.

In Tokyo, commuter trains shut down and trucks were unable to make deliveries to supermarket shelves that ran empty.

Estimates of the economic impact are only now starting to emerge.

As concern about the crippling economic impact of the double disaster mounted, Japanese stocks plunged 7.2 percent to their lowest level in nearly two years, compounding a drop of 7.6 percent the day before.

Hiromichi Shirakawa, chief economist for Japan at Credit Suisse, said in a note to clients that the economic loss will likely be around 14-15 trillion yen (US$171-183 billion) just to the region hit by the quake and tsunami.

Even that would put it above the commonly accepted cost of the 1995 Kobe quake which killed 6,000 people.

The earthquake has forced many firms to suspend production and global companies - from semiconductor makers to shipbuilders - face disruptions to operations after the quake and tsunami destroyed vital infrastructure, damaged ports and knocked out factories.

"The earthquake could have great implications on the global economic front," said Andre Bakhos, director of market analytics at Lec Securities in New York. "If you shut down Japan, there could be a global recession."

- Agencies

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