The International Atomic Energy Agency has discovered that Iran has managed to produce uranium enriched to 84% - far above the purity needed for heat reactor (the type used in a power plant) and a mere 6% short of weapons grade, i.e., of the purity one would need to produce a nuclear weapon. Officially, an investigation is underway to see how that came about - though, clearly, if one thinks of the process involved, of the arduous multi-stage process necessary to produce uranium enriched to a higher grade, one would have a rather hard time imagining how this result could have possibly been achieved by accident.