Jalali repeated earlier claims by others in Iran, including Ahmadinejad, that Stuxnet did not cause major damage or disrupt its nuclear enrichment program because researchers discovered the worm and instituted defenses.
"If we were not ready to tackle the crisis and their attack was successful, the attack could have created tragic incidents at the country's industrial sites and refineries," said Jalali.
He suggested that massive casualties could have resulted, and suggested that they might have been on the scale of the Bhopal, India disaster, where in 1984 a Union Carbide pesticide plant released chemicals that killed between 4,000 and 8,000 people.
Symantec, however, has said that Stuxnet was very successful. In a February update to its research on the worm, Symantec said the first attacks in June 2009 infected Iranian computers just 12 hours after the worm was compiled. The average time between compilation and infection was 19 days for the 10 successful attacks Symantec monitored over an 11-month span.
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