(CNN) -- Workers continued efforts to cool down fuel rods inside two nuclear reactors Sunday as a Japanese government official warned that a second explosion could occur at the plant.
The aftermath of the devastating earthquake -- from the scores of casualties to the nuclear concerns at the plant in Fukushima prefecture -- marks the "toughest and most difficult crisis for Japan" since the end of World War II, Japanese Prime Minister Naoto Kan said Sunday.
Chief Cabinet Secretary Yukio Edano said an explosion could take place in the building housing the No. 3 reactor at the Fukushima Daiichi plant in northeastern Japan.
"There is a possibility that the third reactor may have hydrogen gas that is accumulating in the reactor (that) may potentially cause an explosion," he said.
An explosion caused by hydrogen buildup Saturday blew the roof off a concrete building housing the plant's No. 1 reactor, but the reactor and its containment system were not damaged in the explosion.
http://edition.cnn.com/2011/WORLD/as...lear.reactors/