International sanctions stopped Iran from obtaining anti-virus software, according to a senior Iranian intelligence official. As a result, an estimated 16,000 computers were infected by the Stuxnet virus, a cyber pandemic that has taken years to clean out.

According to a report Saturday by the semi-official FARS news agency, a deputy intelligence chief identified as “Ahangaran” said Iran is being forced to design its own anti-virus software due to the sanctions.

He did not say whether the Stuxnet virus affected only computers within Iran, or whether the virus has infected computers outside the country as well.

However, it is known that the malware seriously damaged computers that controlled centrifuges involved in nuclear fuel production.

The virus, specifically designed to target Iran’s nuclear facilities and other industrial sites, was created in 2010.

Gholam Reza Jalali, director of the Iranian “Passive Defense” military unit that combats sabotage, claimed last week the country’s nuclear facilities are “immune to cyber attacks.”

Two more espionage viruses were recently uncovered by Iranian officials, ABC News reported. The Stars virus embeds itself in the file systems of government institutions, and the Duqu virus gathers information.