JAPAN continues to grapple with a potential nuclear catastrophe after a fire continued to blaze at the stricken Fukushima plant last night.

The fire flared up again at the Unit 4 reactor following three previous explosions.

As panic mounts of a nuclear meltdown, some residents of Tokyo began to flee the capital and surrounding areas with other rushing to shops to stock up on essential supplies.

Japanese authorities have moved to allay fears by ordering some 140,000 residents within 30km of the nuclear plant to stay indoors. A 30km no-fly zone has also been imposed around the reactors.

The nuclear accident is the world’s most serious since the Chernobyl disaster in Ukraine in 1986.

In a nationally televised statement, Prime Minister Naoto Kan urged people in the area to remain calm amidst mounting panic in the region, but admitted that radiation levels had “risen considerably” on the east coast.

“I know that people are very worried but I would like to ask you to act calmly,” he said.

This sentiment was echoed by Japan’s chief cabinet secretary Yukio Edano, who said radiation had been released after a fire broke out in the fourth reactor.

“Now we are talking about levels that can damage human health. These are readings taken near the area where we believe the releases are happening. Far away, the levels should be lower. Please do not go outside. Please stay indoors. Please close windows and make your homes airtight,” he warned.

However, despite government assurances, many residents in Tokyo and its surrounding areas were not taking any chances.

Radiation levels in Saitama, near Tokyo, were 40 times the normal level — not enough to cause human damage but enough to raise fears in the capital city of 12 million people. Officials in Tokyo said radiation levels there were 10 times above normal at one stage but posed no threat to human health.

The country’s nuclear safety agency also confirmed that two workers are missing after the most recent explosion at one of the reactors in the stricken nuclear plant. The agency said they were in a turbine area.

Agency officials also said there was a crack in the roof of the Unit 4 reactor building.

Meanwhile, the continuing crisis has sparked a major review of nuclear technology in countries across the globe.

The EU has agreed to conduct “stress tests” to examine if Europe’s 143 nuclear reactors could withstand earthquakes and other emergencies. Some of the reactors are believed to be located in seismic areas.

EU Energy Commissioner Guenther Oettinger said the tests should follow “strict standards” that would be set by the second half of the year.

The crisis has prompted Germany to announce it will close down seven of its older reactors, perhaps permanently. Italy and Poland are to suspend plans to commit to nuclear energy for the time being.

Russian Prime Minister Vladimir Putin has also ordered a review of the future of the country’s atomic sector.

850,000 homes in northern Japan are without electricity and at least 1.5 million are without running water. Tens of thousands of people are missing with the death toll expected to rise well above 10,000.

Nation under threat

- HIGH levels of radiation leaked from the Fukushima plant after a third explosion in the Unit 2 reactor, combined with a fire, hit the plant. Fresh fire broke out in the Unit 4 reactor last night.

- Radiation levels in Tokyo were recorded at 10 times the normal level yesterday evening, but authorities said there was no threat to human health. Despite government assurances, some residents have chosen to flee the city with others engaging in panic buying.

- A powerful aftershock of magnitude 6.0 occurred near Shizuoka, south-west of Tokyo. Media reports said it triggered power failures across Tokyo.

- Japanese authorities have moved to allay fears by ordering about 140,000 residents within 30 kilometres of the nuclear plant to stay indoors.

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