Panahi entered the country on Tuesday by land via Turkey due to flight restrictions, the sources said.
He had been outside Iran to promote his film It Was Just an Accident, which won the Palme d’Or at the Cannes Film Festival and was shortlisted for the Academy Awards.
Panahi had previously said he would return to Iran after the Oscar campaign despite potential risks. “As soon as the campaign ends, I will return to Iran,” he said in a February interview.
The director has faced years of legal pressure in Iran, including a one-year prison sentence issued in absentia on charges of propaganda against the state, along with a two-year travel ban and other restrictions.
Panahi had faced a long-standing travel ban before being able to travel for the film’s international release. His work, often made despite official restrictions, has focused on social and political issues and drawn on his own experiences of detention and surveillance.