Iranian security forces released Mahsa Amini's father on Saturday after briefly detaining and warning him against marking the anniversary of her death, a human rights group said.
A source close to the family confirmed a report by the Norway-based human rights group Hengaw that Amjad Amini was arrested as he was leaving his house in western Iran.
Mahsa Amini's death in police custody a year ago unleashed months of anti-government protests that spiralled into the biggest show of opposition to the authorities in years.
Iranian officials were not immediately reachable by Reuters for comment.


US strikes Iranian launchers on Larak Island
India must uphold water-sharing treaty with Pakistan, international court says
Nepal teams seek hundreds trapped in hydropower tunnels after deadly floods
Italy, Spain extend tit-for-tat border controls after Ceuta migrant surge
