A worker at the crippled Fukushima nuclear plant accidentally turned off power to the four critically damaged reactors yesterday.
It has been revealed that the decontamination of radioactive gases was also halted at the embattled utility due to the human error, Japan's Nuclear Regulation Authority said.
Power failure was blamed in both cases, with the plant's operator claiming that one of its workers accidentally pushed a stop button causing power to be cut to the plant's key systems.
The Tokyo Electric Power Company (Tepco), has been desperately pumping water into the wrecked reactors to cool nuclear fuel that melted when the March 2011 earthquake and tsunami knocked out the plant's power and cooling systems.
Conflicting reports have left many baffled, and nuclear experts have already highlighted that no one really knows the true severity of the radioactive water leaks at Fukushima nuclear plant in Japan.
But Monday's blunder follows a series of preventable oversights by the utility, including workers overfilling a storage tank to the point highly-radioactive water leaked into the adjacent Pacific Ocean, building shoddy, leaking storage tanks to contain massive amounts of toxic wastewater and allowing rodents to short circuit a switchboard, leading to systems to cool spent fuel rods being offline for almost 30 hours.
The utility has built more than 1,000 tanks holding 335,000 tons of contaminated water at the plant, and the amount grows by 400 tonnes daily. Some tanks have already sprung leaks, spilling contaminated water onto the ground.