The No. 2 reactor at the Fukushima power plant may be damaged, according to Yukiya Amano, Director General of the I.A.E.A.:

Yukiya Amano, director general of the International Atomic Energy Agency (IAEA), told a news conference there was a “possibility of core damage” at unit 2. The damage is estimated to be less than 5 percent of the fuel, he said.
He said there was also possible damage in the bottom part of the primary containment vessel, but that this was not confirmed.
“Is it a crack? Is it a hole? Is it nothing? That we don’t know yet,” Amano said. But he said the pressure in the primary containment vessel had not fallen. “If there is a huge damage the pressure should go down.”

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