Radiation exceeding government safety limits has seeped into groundwater under Japan's tsunami-crippled nuclear plant.
Tokyo Electric Power Co. (TEPCO) said Iodine-131, a radioactive substance that decays in a relatively short period, was found nearly 15 meters below one of the reactors.
The groundwater contamination -- 10,000 times higher than the government standard for the plant -- is the latest setback at the Fukushima Daiichi complex.
The company's spokesman said the company doesn't believe any drinking-water supply is affected.
Contaminated water has been pooling at the Fukushima Daiichi nuclear complex since it was damaged by the devastating earthquake and tsunami.
It has already leaked into the ocean, with levels continuing to spike several hundred meters offshore.
compiled from agency reports