The images were captured during a probe of the No.3 reactor by a remote-controlled robot in July.

The probe confirmed for the first time the existence of lumps that are likely to be fuel debris as well as damaged components of the reactor.

Fuel debris is a mixture of melted nuclear fuel and broken reactor parts. It is believed to be accumulating inside the containment vessels of the 3 reactors that underwent meltdowns at the plant.

Tokyo Electric Power Company officials said on Thursday night that one of the images taken just below the pressure vessel of the No.3 reactor shows damaged tube-shaped devices that were used to insert control rods into the reactor.

They said they also confirmed that the cables laid along a supporting structure called a pedestal were severely damaged.

The officials said the cables, which are connected to thermometers, will melt only at temperatures over 1,000 degrees Celsius. They said this could suggest that molten fuel and other objects fell from the reactor and inflicted the damage on the cables.

Tokyo Electric plans to conduct further analyses as part of its efforts to work out ways to remove the fuel debris. The removal is an important step toward decommissioning the disabled plant.