The Japanese decision to focus their efforts Thursday on the No. 3 
reactor appeared to suggest that officials believe it is a greater 
threat, since it is the only one at the site loaded with a mixed fuel 
known as mox, for mixed oxide, which includes reclaimed plutonium. 

日本は全く言わないよな(;´Д`)3号機がプルトニウム入りだってことを

http://www.nytimes.com/2011/03/18/world/asia/18nuclear.html?_r=1&hp