The operator of Japan’s Fukushima nuclear plant says at least 45 tonnes of highly radioactive water has leaked from the facility, possibly into the Pacific Ocean.
A statement by the operator TEPCO said workers noticed a leak in a purification device, with radioactive water escaping through a crack in a catchment wall.
The leaking water contained about 1 million times as much strontium as the maximum safe level.
Strontium is easily absorbed by living tissue and can cause cancer.
TEPCO says some of the 45 tonnes or more of contaminated water may have reached the Pacific Ocean.
Last week, TEPCO reported that molten fuel rods at the plant may have eaten two-thirds of the way through a concrete containment base.
The statement was based on a new simulation of the March meltdowns.
It said the latest calculations suggest the nuclear fuel inside the No. 1 reactor has melted entirely.
Simulations predict the molten fuel has eaten through 65 centimetres of concrete in a containment base below, stopping just 37 centimetres short of an outer steel casing.
It is also believed the molten core has eaten part of the way through the concrete bases of the No. 2 and 3 reactors.
The findings indicate the facility came much closer to a cataclysmic meltdown than previously thought.
