Explosion, radiation leakage rock Japan nuclear plant

Chief Cabinet secretary says "we are looking into cause" of blast at Tokyo Electric Power Co facility as fears of reactor meltdown grow; reports suggest at least 4 people injured; evacuation area expanded.

By REUTERS
Japan nuclear explosion 311 (photo credit: REUTERS/NTV via Reuters TV)
Japan nuclear explosion 311
(photo credit: REUTERS/NTV via Reuters TV)
Japanese Chief Cabinet Secretary Yukio Edano confirmed on Saturday there has been an explosion and radiation leakage at Tokyo Electric Power Co's (TEPCO) Fukushima Daiichi nuclear power plant.
"We are looking into the cause and the situation and we'll make that public when we have further information," Edano said. "At present, we think 10 km evacuation is appropriate."
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The explosion injured at least four workers at the plant, Japanese officials said, according to ABC news.
The Japanese government said it has expanded the evacuation area around the power plant to a 20 kilometre radius from 10 km.
Japan earlier in the day warned of a meltdown at a reactor at the plant, damaged when a massive earthquake and tsunami struck the northeast coast, but said the risk of radiation contamination was small.
Jiji news agency said there had been an explosion at the stricken 40-year-old Daichi 1 reactor and TV footage showed vapour rising from the plant, which lies 240 km (150 miles) north of Tokyo.
Pressure was building in reactors of two plants at Tokyo Electric Power Co 's Fukushima facility, located some 240 km (150 miles) north of Tokyo. At one of them, the Daiichi plant, pressure was set to released soon , which could result in a radiation leak, officials said.
"It's possible that radioactive material in the reactor vessel could leak outside but the amount is expected to be small, and the wind blowing towards the sea will be considered," Chief Cabinet Secretary Yukio Edano told a news conference.
"Residents are safe after those within a 3 km radius were evacuated and those within a 10 km radius are staying indoors, so we want people to be calm," he added.
A trade ministry official said that TEPCO was also considering releasing pressure at its other plant, the Daini plant.
TEPCO said it had lost ability to control pressure in some of the reactors at the Daini plant as it had with the Daiichi plant. Pressure wa s stable inside the reactors of the Daini plant but rising in the containment vessels, a spokesman said.