The operator of the Fukushima Daiichi nuclear power plant says it has detected the highest confirmed indoor level of radioactivity at the facility since the March accident.
The Tokyo Electric Power Company, or TEPCO, said on Tuesday that the level in a room on the second floor of the Number One reactor building was 5,000 millisieverts per hour.
TEPCO says the level was detected because pipes running through the room were used to vent air containing radioactive substances from the reactor on March 12th.
On Monday, a level of 10,000 millisieverts per hour was detected near pipes outside the building.
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