Safety Concerns Arise from Latest Fukushima Reactor Images.

New images captured by a robotic probe inside one of the three melted reactors at Japan's Fukushima nuclear power plant showed exposed steel bars in the main supporting structure and parts of its thick external concrete wall missing, triggering concerns about its earthquake resistance in case of another major disaster. About 880 tons of highly radioactive melted nuclear fuel remain inside the three reactors, and the status of the melted debris is still largely unknown. TEPCO plans to further analyze data and images over the next couple of months to find out if and how the reactor's earthquake resistance can be improved.