Robots sent in to explore the Fukushima No. 1 nuclear plant have found high radiation levels in three reactor buildings that may seriously hinder efforts to bring the plant under control, Japan's nuclear watchdog said Monday.
On Sunday, two U.S.-made robots checked radiation, temperature and oxygen concentrations in reactors 1 and 3 to see if they were safe for repair crews to enter to get the crippled cooling systems back online
In the No. 3 reactor building, the robots detected a radiation level of 28 to 57 millisieverts per hour on the ground floor.