Iranian security services have arrested several "spies" in Bushehr province, where the country's sole nuclear plant is based, Intelligence Minister Mahmoud Alavi announced Tuesday.
"Thanks to the vigilance of the ministry, which monitors the movements of foreign intelligence services, agents who wanted to carry out surveillance and collect information... in Bushehr province have been identified and brought to justice," said Alavi.
He did not elaborate on the number of people arrested or their nationality.
"This province is a hub for the country's economy, industry, military, and commercial and nuclear sectors and has a special position at the national level," Fars news agency quoted him as saying on a visit to the region.
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The nuclear power plant in Bushehr, which produces 1,000 megawatts of electricity, was constructed by Russia after being delayed for years and handed over to Iran in September 2013.
Iran plans to build 20 more plants in the future, including four in Bushehr alone.
In recent years, the Islamic republic has detained a number of alleged US or Israeli agents accused of spying on, or attempting to sabotage, its nuclear programme.
In August 2012, saboteurs blew up power lines supplying Iran's underground uranium enrichment plant at Fordo outside the central city of Qom.
In 2010, a cyber-attack hit Iran's nuclear facilities. The Stuxnet virus was tailored specifically to target uranium enrichment facilities.
A number of Iranian nuclear engineers have also been killed in what Tehran says were assassinations by foreign intelligence services.