Fukushima/Tokyo, Mar 16 : Radiation levels rose today in Japan's Fukushima nuclear plant where a new fire broke out, forcing the government to withdraw emergency workers engaged in efforts to cool overheating reactors at the quake-stricken site as authorities scrambled hard to contain the spiralling atomic crisis.
Some 50 employees were believed to be working at the plant, 220 km north of Tokyo, to avert a meltdown when the radiation levels surged suddenly.
The government's nuclear safety agency said the radiation levels briefly reached 10 millisievert per hour at the plant's entrance at 10:40 am local time, but added that it was possibly due to radioactive substances emitted from the No. 2 reactor.
Authorities were also considering spraying boric acid by helicopters to prevent spent nuclear fuel rods at another troubled reactor, No.4, from reaching criticality again, restarting a chain reaction, Kyodo news agency reported.
Around 730 workers were evacuated from the site yesterday following hydrogen explosions at the reactors, according to Tokyo Electric Power Company (TEPCO), the operator of the plant.
The remaining employees at the Fukushima Daiichi plant were withdrawn today following the sudden rise in radiation levels, Chief Cabinet Secretary told a news briefing.
The work was suspended temporarily at the plant, where an estimated 70 per cent of the nuclear fuel rods have been damaged at the No.1 reactor and 33 per cent at the No.2 reactor.
"Workers cannot carry out even minimal work at the plant now. Because of the radiation risk, we are on standby," Edano said.
The cores of both reactors are believed to have partially melted with their cooling functions lost in the wake of Friday's magnitude 9.0 earthquake and massive tsunami that have left over 11,000 people dead or unaccounted for.
At the No.2 reactor, the pressure-suppression chamber connected to its containment vessel was damaged following an explosion yesterday.
Earlier today, a fire broke out again at the No.4 reactor, which was already posing the risk of leaks of high-level radioactive material, but flames were no longer visible about 30 minutes later, according to TEPCO.
The No.3 reactor was, however, drawing more attention after live TV footage of the plant showed white smoke coming out around 10 am local time, Kyodo reported.
"There is a possibility that the No.3 reactor's containment vessel is damaged," Edano said, indicating that radioactive steam may be spreading outside.
He, however, said the government had no plans to expand the evacuation area of within 20 kilometers from the plant for now.
In a rare address to nation, Japan's Emperor Akihito said he was deeply concerned about the nuclear crisis.
"I am deeply concerned about the nuclear situation because it is unpredictable," he said in the televised address. "With the help of those involved I hope things will not get worse."
77-year-old Akihito called for an all-out rescue operation in the quake-ravaged region, while thanking all those involved in relief work, including foreign countries.
"We don't know the number of victims, but I pray that every single person can be saved," he said.
Rescue operations were, meanwhile, continuing in the quake-hit region, with 80,000 Self-Defense Forces personnel and police officers being mobilised for the purpose.
Officials said over 11,000 people were killed or unaccounted for, with the National Police Agency confirming 3,676 deaths in 12 prefectures.
An estimated 7,843 people remained unaccounted for in six prefectures, the officials said, adding The death toll, however, is likely to climb.
However, BBC said that in the north-eastern town of Otsuchi alone, the fate of half of the population - around about 8,000 people - remains unknown.
Some 530,000 people have been staying in more than 2,600 shelters, prompting the severely-hit prefectural governments of Iwate, Miyagi and Fukushima to request Japan Prefabricated Construction Suppliers and Manufacturers Association to build 32,800 temporary housing in total, Kyodo said.
Immigration authorities, meanwhile, decided to provide information on foreign nationals staying in Japan, including on their fingerprints, if necessary, to local governments to check their whereabouts or identify them.
The Justice Ministry's Immigration Bureau also said it has decided to accept inquiries on whether foreign nationals who had been staying in the quake-hit Aomori, Iwate, Miyagi and Fukushima prefectures had left the country, to help their families and friends know about their fate. Inquiries can be made by telephone, fax or e-mails.
In a bid to cover an acute electricity shortage, TEPCO carried out rolling blackouts for the third consecutive day by cutting off electricity in the Tokyo vicinity.
Many people rendered homeless following the quake are enduring snow and freezing temperatures. Aftershocks also continued to rock Japan, with a strong quake with a preliminary magnitude of 6.0 jolting Tokyo and its vicinity today.
The Bank of Japan has offered an additional 13.8 trillion yen (some USD 170 billion) to money markets, bringing to 55.6 trillion yen the total emergency funds made available by it to protect the nation's banking system from the negative impact of Friday's massive earthquake. PTI
