Renowned cartoonist Hadi Heidari who contributes to several reformist newspapers and heads the website Persian Cartoon was arrested in the capital Tehran on the evening of October 22.
He was among several people arrested while taking part in a religious ceremony in honour of political prisoners, held at the home of Shehaboldin Tabatabai, one of the prisoners close to the reformist party, Participation.
Some of them were released the following day but around a dozen others, including Heidari, were moved to Evin prison.
Heidari was cultural editor of the banned daily Etemad-e Melli. The editor of the newspaper, Mohammad Ghochani, a member of its editorial staff, Fayaz Zahed, and website editor, Mohammad Davari, are all still in prison.