Tokyo Electric Power Co. said Thursday that radiation levels of up to 9.4 sieverts per hour have been detected outside a reactor containment vessel at the meltdown-hit Fukushima No. 1 nuclear power plant. People exposed to the maximum radiation dose for some 45 minutes will die.

Tepco expects decontamination work to take at least one month. Sept. 4-25 checks found the extremely high radiation levels at a cell that accommodates a pipe connected to the containment vessel of reactor 2 at the plant, which was devastated by the March 2011 earthquake and tsunami, Tepco said. The highest contamination was detected on the floor. Details behind the situation are unknown, according to the company. Tepco planned to start in August to check the inside of the containment vessel by using a remote-controlled robot but high radiation levels have stalled the examination. FULL REPORT