Radiation-contaminated water leaked from a desalination facility at Japan’s stricken Fukushima nuclear plant on Wednesday, operator Tokyo Electric Power Co said.
Six of the 11 workers at the scene were likely covered with the tainted water, the Nuclear Regulation Authority said.
The workers accidentally disconnected a pipe to the desalination facility, which caused a leak for more than 50 minutes in the morning at the Fukushima Daiichi Nuclear Power Station, TEPCO said.
About 10 tonnes of water may have leaked, but did not reach the sea, the operator said.
The plant suffered meltdowns at three of its six reactors after a tsunami swept through the complex in March 2011.
Tokyo Electric has been battling with leaks at the plant as it continues to inject water into the three reactors to keep them cool.
The cooling water is then put through facilities that reduce its radioactive content and remove salt before it is stored in tanks at the site.
In late August, about 300 tonnes of radiation-contaminated water leaked from a storage tank, some of which could have flowed into the Pacific Ocean, the operator said.