Crisis deepens at quake-hit Japan nuclear plant

TOKYO : Japan's nuclear crisis deepened on Wednesday with another fire at a quake-hit atomic power plant and a radiation spike there that forced the temporary evacuation of workers.

Military helicopters carrying giant buckets were preparing to drop water on the stricken plant, which has been hit by four explosions and two fires since last Friday's earthquake and tsunami knocked out cooling systems.

But media reports quoting defence ministry officials said the attempt was postponed because of high radiation levels over the Fukushima No. 1 plant, 250 kilometres (155 miles) northeast of Tokyo.

Scared Tokyo residents filled outbound trains and rushed to shops to stock up on face masks and emergency supplies, amid fears of radiation headed their way. Some foreign residents have also pulled out.

The radiation level in the mega-city was normal on Wednesday, officials said. Levels had risen on Tuesday but not to a degree hazardous to health.

Chief government spokesman Yukio Edano made an apparent attempt to ease fears in the face of mounting overseas concern.

He said radiation poses no immediate health threat outside a zone within 20 kilometres (12 miles) of the plant which has already been evacuated.

"I have been informed that the figures monitored today (outside the zone) were not anything that would harm human health immediately," Edano told a briefing.

The day began with a pre-dawn blaze at the plant's number-four reactor. This apparently died out of its own accord, but in mid-morning, a cloud of smoke or steam was seen rising from the number three reactor.

Radiation levels then rose sharply at the plant - prompting a brief evacuation of workers - but fell soon afterwards.

Edano said the most likely explanation for the sudden rise was an emission of radioactive steam from the number three reactor's containment vessel,
although he stressed nothing had been confirmed.

There was no need at present to expand the evacuation zone around the plant, he said. At 4:00pm (0700 GMT) the radiation level was stable around 1.5 millisieverts near the front gate, the spokesman said.