A remote-controlled robot on Tuesday was used to probe the hardest-hit nuclear reactor at Japan s wrecked Fukushima plant, as officials push forward with clean-up operations that have been mired in delays and controversy.
An earthquake and tsunami in 2011 unleashed a disastrous meltdown at Fukushima Daiichi's three reactors that partly sunk their radioactive cores into the plant's concrete foundations, making removal extremely difficult.
