TOKYO (Kyodo) -- Tokyo Electric Power Co. said that a pump to inject water into one of the severely damaged reactors at the Fukushima Daiichi nuclear power plant halted Monday, possibly due to a problem at a power switchboard.
The halt occurred at around 9:47 a.m. But cooling of the No. 1 reactor immediately resumed through a backup pump, the utility known as TEPCO said.
The Nuclear Regulation Authority separately said in a press release that the incident may have occurred because a worker wrongly pushed the stop button on a switchboard during an equipment checkup.
At the Fukushima plant in northeastern Japan, the Nos. 1 to 3 reactors suffered meltdowns in March 2011 because quake-triggered tsunami waves that hit the plant flooded electrical equipment and led to the loss of reactor cooling systems.