Funny, it isn't unexplained to me;
International Atomic Energy experts have found unexplained plutonium and highly enriched uranium traces in a nuclear waste facility in Iran and have asked Tehran for an explanation, an IAEA report said Tuesday.
But, hey, don't worry because:
The first cracks in the united front over Iraq between Tony Blair and President Bush appeared last night as the Prime Minister offered Iran and Syria the prospect of dialogue over the future of Iraq and the Middle East.
I find it interesting that they've got enough plutonium to have some thrown away.