TEHRAN — In a preliminary ruling, Iran’s revolutionary courts convicted American Amir Mirzaei Hekmati, 28, of working for the CIA and sentenced him to death, the Fars news agency reported Monday.

The report said Hekmati was also convicted of trying to accuse Iran of involvement in terrorism.

Hekmati allegedly confessed on state television that he had been trained in the U.S. “and planned to imply that Iran was involved in terrorist activities in foreign countries” after returning to the U.S., AP reported.

Hekmati’s father, who lives in Michigan, says the former U.S. Marine was working as a translator and had gone to Iran to visit his grandmother when he was arrested.

Hekmati is a dual U.S.-Iranian national. Iran considers the Arizona-born Hekmati an Iranian since the country’s law does not recognize dual citizenship. AP reported.

Iranian law gives Hekmati 20 days to appeal the decision.

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