Feb 2 (Reuters) - More than 8 tonnes of water have leaked from Japan's stricken nuclear power plant after a frozen pipe burst inside a reactor buiding, but none of the water is thought to have escaped the complex, Kyodo news agency said on Thursday.
Kyodo, quoting the Fukushima plant's operator Tokyo Electric Power Co (Tepco), said the water had leaked from the No.4 reactor when a pipe "dropped off" but that the liquid had all been contained inside the reactor building.
The plant, on the coast north of Tokyo, was wrecked by a huge earthquake and tsunami in March last year, triggering the evacuation of around 80,000 people in the world's worst nuclear crisis in 25 years. The major leak follows the discovery and plugging of smaller leaks at the same reactor last weekend.
Kyodo quoted Tepco officials as saying the latest leak had been found late on Tuesday night and was stopped by closing a valve. The report did not make completely clear if the leaked water was radioactive but implied it, noting that water inside the No.4 reactor was being used to cool spent fuel rods.
"The total amount of leakage from the reactor was initially estimated to be 6 litres, but the utility revised the figure later Wednesday, adding that the leakage appears to have started at around 5 p.m. (0800 GMT) Monday," Kyodo said.
"The utility plans to check whether there are similar cases in the other crippled reactors," it added. (Reporting by Mark Bendeich; Editing by Kavita Chandran)