Iranian officials admitted Sunday that they had uncovered evidence of the Duqu computer virus -- labeled "Son of Stuxnet" by cyber experts -- at the Islamic Republic's nuclear sites, state-controlled IRNA news agency reported.

"We are in the initial phase of fighting the Duqu virus," Gholamreza Jalali, was quoted as saying. "The final report which says which organizations the virus has spread to and what its impacts are has not been completed yet."

The original Stuxnet malware was the culmination of a vast technical and espionage effort that had only one target in mind: the Iranian nuclear program. And is widely believed to be the work of the United States and Israel. Experts who looked at the program were amazed at its ability to penetrate Iran’s secure, highly protected security system and destroy it without being detected.