TEHRAN, Iran—A months-long delay in starting up Iran's first nuclear power plant is the result of a small leak, not a computer worm that was found on the laptops of several plant employees, the country's nuclear chief said Monday.
The leak occurred in a storage pool where the plant's fuel is being held before being fed into the reactor core, and it has been fixed, said Ali Akbar Salehi, who is also Iran's vice president. He did not specify whether it was nuclear fuel or another material that leaked. He first announced the delay on Thursday but without giving a reason.
Iranian officials say they have vigorously battled the Stuxnet computer worm, which they suspect is part of a covert plot by the West to damage Iran's nuclear work. The United States, Israel and others accuse Iran of seeking to use the Bushehr power plant and other civil nuclear sites as a cover for a secret program to develop atomic weapons.
Iran denies any nuclear weapons ambitions and says its program is only for peaceful purposes like power generation and medical research.
The malicious computer code, designed to take over industrial sites like power plants, has also emerged in India, Indonesia and the U.S. But it has spread the most in Iran.
Though it infected several personal computers of workers at the Bushehr plant, Iran says the facility's main systems were not affected. Still, that was the first public sign to emerge that the code has hit computers linked to Iran's nuclear program.
The delay at Bushehr has no connection with Stuxnet, Salehi said, according to a report in the official IRNA news agency.
"During a washing process prior to loading the actual nuclear fuel, a small leak was observed in a pool next to the reactor and was fixed. This leak delayed activities for a few days," IRNA quoted Salehi as saying.
At the plant's inauguration on Aug. 21, Salehi had said loading the fuel into the reactor core would take place over two weeks and the plant would then produce electricity two months later in November.
Now, he says, fuel will be transferred to the core in mid-October and that the plant will produce electricity in early 2011.
Iran's deputy industry minister, Mohsen Hatam, said technicians have removed the Stuxnet malware from all affected systems in Iranian industry.
"All (infected) platforms have been scanned, cleaned and sent back to their respective industries," Hatam was quoted as saying by state TV on Sunday.
In a progress update a day earlier, Intelligence Minister Heidar Moslehi also announced the arrests of several nuclear spies, but he gave no details and did not clearly link the suspects with the investigation into Stuxnet.
Who created the Stuxnet code and what its precise target is, if any, remains a mystery. Some foreign experts have speculated it was designed to target Tehran's nuclear program.
The web security firm Symantec Corp. says the computer worm was likely spawned by a government or a well-funded private group. It was apparently constructed by a small team of as many as five to 10 highly educated and well-funded hackers, Symantec says.
The Bushehr plant has stood outside the current controversy over Iran's nuclear program since Russia will be providing the fuel for the plant and supervising its disposal.
But other aspects of Iran's nuclear work, especially its enrichment of uranium, are of concern to the United States and other world powers. Enrichment can be used to produce weapons as well as make fuel for power plants.