The operator of the disaster-hit Fukushima No. 1 nuclear power plant said Wednesday it has completed its first attempt to use a remote-controlled probe to manipulate melted fuel accumulating at the bottom of one of the crippled reactors.

During the nearly eight-hour operation, Tokyo Electric Power Company Holdings Inc. inserted the probe that is equipped with a camera, radiation meter and tong-like grips into the primary containment vessel of the No. 2 reactor.

Of the six locations that were surveyed, the probe, which is 30 cm tall and 10 cm wide, successfully lifted several centimeters of deposits at five locations, a Tepco official said at a news conference. The deposits in many of those areas resembled gravel.