Three workers at the Fukushima Daiichi nuclear power plant have been exposed to high levels of radiation after reportedly stepping into contaminated water as they battled to make the stricken No 3 reactor safe, London's Guardian reports.

Two of workers were taken to a special radiation unit at a hospital in Chiba city, east of Tokyo, Japan's nuclear safety agency said.

The workers, who are all in their 20s and 30s, were exposed to between 170 millisieverts and 180 millisieverts of radiation. This is above the usual legal limit of 100 millisieverts per year for nuclear power workers in Japan, but below a new limit of 250 millisieverts, introduced last week to enable them to spend more time inside the crippled facility.

The men were affected while laying cable in the turbine building of the No 3 reactor, said Fumio Matsuda, an agency spokesman, adding that two had exposed skin on their feet to radioactive elements. The condition of the men taken to hospital was not immediately clear.

Their condition cast doubt on the wisdom of raising the threshold for radiation exposure for the hundreds of technicians, firefighters and soldiers taking part in the Fukushima operation.

The government' chief spokesman, Yukio Edano, said the injuries were "very regrettable", but defended the health ministry's decision to raise the exposure limit soon after the start of the world's worst nuclear power emergency since Chernobyl.

"Atmospheric radiation levels are monitored constantly, but in this case the workers stepped into water," Edano said.

Read the entire story at guardian.co.uk