A US man of Iranian extraction has been sentenced to death for spying for the CIA, the Fars news agency reported.
Born in the US to an Iranian immigrant family, Amir Mirzayi Hekmati, 28, admitted on an Iranian state television programme that he was a CIA operative.
Although he had been arrested months earlier, his family in the US continued to maintain that he was not spying at the time and had travelled to Iran to visit his grandmother.
"Amir Mirzayi Hekmati was sentenced to death for co-operating with the hostile country [the United States] and spying for the CIA," Fars said, without quoting a source. "The court found him corrupt."
The prosecutor relied on Hekmati's public confession to claim he attempted to breach the intelligence ministry by pretending to be a disaffected former US soldier with secret information.
The US has demanded Hekmati's release. The state department said Iran has not permitted diplomats from the Swiss embassy, which handles US interests in the absence of US-Iran ties, to see Hekmati before or during his trial.
Meanwhile, Associated Press reported that Iran has begun to enrich uranium at a new underground site, which is believed to be shielded from possible airstrikes.
The Daily Kayhan reported that Iran has begun injecting uranium gas into centrifuges at the Fordo facility near the holy city of Qom.
Iran also has a major uranium enrichment facility in Natanz in central Iran, where nearly 8,000 centrifuges are in operation.