VIENNA — The control systems of Iran's Bushehr nuclear plant have been penetrated by a computer worm unleashed last year, according to a foreign intelligence report obtained by the Associated Press that warns of a possible Chernobyl-like disaster once the site becomes fully operational.
Russia's envoy to NATO, Dmitry Rogozin, also has raised the specter of the 1986 reactor explosion in Ukraine, but suggested last week that the danger had passed.
Chernobyl's reactor No. 4 exploded in 1986, spewing radiation over a large stretch of northern Europe. Hundreds of thousands of people were resettled from areas contaminated with radiation fallout in Ukraine, Belarus and Russia. Related health problems still persist.
The intelligence report, drawn up by a nation closely monitoring Iran's nuclear program, said that with control systems disabled by the virus, the Bushehr reactor would have the force of a "small nuclear bomb."
"The minimum possible damage would be a meltdown of the reactor," it says. "However, external damage and massive environmental destruction could also occur … similar to the Chernobyl disaster."
The virus, known as Stuxnet, has the ability to send centrifuges spinning out of control and temporarily crippled Iran's uranium enrichment program late last year. Some computer experts believe Stuxnet was the work of Israel or the United States, two nations convinced that Iran wants to turn nuclear fuel into weapons-grade uranium.
Iran has acknowledged that the malware — malicious software designed to infiltrate computer systems — hit the laptops of technicians working at Bushehr, but has denied that the plant was affected or that Stuxnet was responsible for delays in the startup of the Russian-built reactor.
Iran says its nuclear activities are aimed at generating energy, but they are under U.N. sanctions because of concerns they could be channeled toward making weapons.
Ali Asghar Soltanieh, Iran's chief representative to the International Atomic Energy Agency, cut short attempts by AP to seek comment on possible damage by Stuxnet at Bushehr.
Experts are split on how powerful the Stuxnet virus might prove. A spokeswoman for Atomstroyexport, the Russian company in charge of construction at Bushehr, also cast doubt on there being major damage at the plant, saying its control system is fully autonomous and virus-proof.
The IAEA declined comment.