Workers wearing protective suits and masks carry out an operation to remove fuel rods from a spent fuel pool inside the No.4 reactor building at Tokyo Electric Power Co's (TEPCO) Fukushima Daiichi nuclear power plant in Fukushima prefecture November 18, 2013, in this handout photograph taken and released by TEPCO. TEOPCO began on Monday removing 400 tonnes of the dangerous spent fuel in a hugely delicate and unprecedented year-long operation fraught with risk. Mandatory credit. [Photo/Agencies]