Iranian authorities indicted a French tourist on charges of spying and spreading propaganda against the system, his lawyer said on Sunday.
This is the latest in a series of cases against foreign visitors amid heightened tensions between Iran and the West.
Benjamin Briere was arrested in May last year after flying a drone and taking photos in a desert area where photography is prohibited and asking questions "in the media" about Iran's obligatory Islamic headscarf for women.
Under Iranian law, a spying conviction can bring up to 10 years in prison and a conviction on a charge of spreading propaganda against the system can be punishable by three months to a year.
Briere's indictment was handed up by the justice department in the northeastern city of Mashahd. It wasn't immediately clear when his trial would take place.
Rights groups accuse hard-liners in Iran's security agencies of using foreign detainees as bargaining chips for money or influence in negotiations with the West. Tehran denies it, but there have been prisoner exchanges in the past. Last year, Iran and France swapped French researcher Roland Marchal for Iranian engineer Jalal Ruhollahnejad.
"Benjamin has spent more than a year in prison and has only now been officially charged with 'espionage,' said Kylie Moore-Gilbert of Melbourne University's Asia Institute.
"He has been allowed 4 phone calls with his family in 12 months."
Briere is the latest Westerner to be held on widely criticized espionage charges.
The incident mirrors the plight of Australian backpackers Joely King and Mark Firkin, who were arrested at Evin in 2019.
Iran confirmed they had arrested the couple who ran the blog and instagram page @TheWayOverland, after they were found to be taking photos and videos from the Iranian border.
The couple were freed following the return of Queensland academic Dehbashi Kivi prisoner to Tehran, although Australian attorney general Christian Porter could not confirm this was part of an exchange.
"The Australian government does not comment on the details behind its consideration of particular cases," he told the Guardian.
In March, prominent British-Iranian dual national Nazanin Zaghari-Ratcliffe reappeared in a Tehran court to face similar accusations of spreading propaganda after completing a five-year prison sentence. She remains in limbo in Iran awaiting a verdict, unable to return to London.
The cases come as Iran escalates pressure on the United States and European powers, including France and Britain, to grant badly needed relief from sanctions. Harsh sanctions were reimposed on Iran after the US withdrew from Iran's nuclear accord with world powers in 2018.
President Joe Biden has since joined in talks aimed at restoring the deal. But Washington and Tehran have reached an impasse, with each insisting the other move first to revive the deal.
- Associated Press with additional reporting