Iranian authorities have asked award-winning filmmaker Mohammad Rasoulof to report to the prosecutor's office after confiscating his passport upon arrival in Tehran.
Rasoulof's passport was taken away at Tehran's airport on September 15 as he returned from the United States, where he had screened his latest film, A Man Of Integrity (Lerd), at the Telluride film festival.
Rasoulof, 45, who has previously been jailed for "antiregime propaganda," was then "invited" to present himself in person to the prosecutor for media and culture, Kaveh Farnam, who co-produced the prize-winning film, told AFP.
He said Rasoulof would probably go "next week", adding, "We have no idea what's going on."
A Man Of Integrity won the top prize in one of the sections of this year's Cannes Film Festival.
The film tells the story of a man working at a goldfish farm who becomes ensnared in corruption.
After the award was announced, Rasoulof told Reuters: "I love Iran, but it is like an alcoholic father. Sometimes it hits me."
In 2010, Rasoulof was sentenced to six years in prison for a documentary about the protests over the disputed 2009 Iranian presidential election.
However, his sentence was subsequently reduced to one year in prison.