Iran's uranium enrichment activities came to a complete halt for at least one day earlier this month, a new restricted United Nations report revealed Tuesday, amid speculation the activities were the target of a cyber attack.
"On Nov. 16, no cascades [of uranium-enriching centrifuges at Iran's Natanz enrichment nuclear plant] were being fed with UF6 [uranium hexaflouride]," the International Atomic Energy Agency wrote in a restricted new report, a copy of which was obtained by AFP.
On a prior visit Nov. 5, IAEA inspectors had verified that more than 4,800 such centrifuges were being fed with nuclear material. And almost the same number were up and running again Nov. 22.
There was no indication yet how long the outage lasted, of whether it was longer than just one day, according to a senior diplomat familiar with the IAEA's investigation.
The IAEA report didn't contain any explanation about the possible reasons for the outage, and the diplomat also refused to speculate that it was caused by a computer worm, called Stuxnet, which has infiltrated Iran's nuclear facilities recently.
Last week, the computer security firm Symantec Corp. (SYMC) said Stuxnet may have been specifically designed to disrupt the motors that power gas centrifuges used to enrich uranium. That has given rise to speculation the worm was intended to sabotage nuclear facilities in Iran, especially the Russian-built atomic power plant in the southern city of Bushehr.