By Chris Meyers
KORIYAMA, Japan, March 13 (Reuters) - Thousands of people evacuated from areas around a crippled nuclear power plant were scanned for radiation exposure as Japanese authorities struggled to cope with the aftermath of a massive earthquake and tsunami.
Although the government insisted radiation levels were low following an explosion in the main building of the plant, 240 km (150 miles) north of Tokyo, officials ordered an evacuation zone doubled to a radius of 20 km (12 miles) around the site.
At evacuation centres, workers wearing white masks and protective clothing used handheld scanners to check everyone arriving for radiation exposure.
"There is radiation leaking out, and since the possibility (of exposure) is high, it's quite scary," said 17-year-old Masanori Ono, queuing at a centre in Koriyama city, in Fukushima prefecture.
People who lived within the evacuation zone or showed signs of radiation exposure were separated from others seeking shelter.
Japan's nuclear safety agency said the accident at the 40-year-old Daiichi 1 reactor plant in Fukushima prefecture, which was triggered by Friday's 8.9 magnitude earthquake, was less serious than both the Three Mile Island accident in 1979 and the 1986 Chernobyl disaster.
But 90,000 people had been evacuated from areas near the plant while authorities prepared to distribute iodine to people in the vicinity who may have been exposed. Iodine can help protect against thyroid cancer following exposure to radiation.
At one emergency centre, a baseball practice facility in Koriyama, dozens of people huddled under blankets and tried to sleep.
The blast had raised fears of a meltdown at the power plant, but experts said pictures of mist above the facility suggested only small amounts of radiation had been released.
That was little comfort for some of those queuing in the freezing night.
"My home is in Minami Soma and I still have people who I haven't been able to contact and there have been reports of the nuclear leak. I'm really concerned about their safety," said 31-year-old entrepreneur Yohei Yonekura. (Writing by Alex Richardson; Editing by Dean Yates)
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