TOKYO: The operator of Japan’s stricken Fukushima nuclear plant said Friday it is using an underwater robot in a renewed attempt to inspect damage suffered in a tsunami-induced meltdown. Tokyo Electric Power Co (TEPCO) in February sent a remote-controlled robot into one of three damaged reactors where radiation levels have hit record highs.But the mission was aborted at the No. 2 reactor after the robot could not reach its target destination beneath a pressure vessel through which nuclear fuel is believed to have melted as the robot had difficulty moving.Locating the fuel debris is part of the decommissioning process for the plant expected to take decades.On Wednesday, TEPCO sent a robot measuring 13 centimeters (5.1 inches) wide and 30 centimeters long to the No. 3 reactor and conducted another inspection on Friday, a spokesman said. But the company has yet to find the fuel debris.”Today the robot went deeper inside the containment vessel” of the reactor, he said, referring to the Friday probe, adding that TEPCO will analyze the images.