Police in Tehran attacked 3,000 protesters supporters of a spiritual group gathered in peaceful protest outside the city's Revolutionary Court before the trial of their faith's founder.
Intelligence Ministry agents used tear gas on the crowd, and arrested some who were transported to an unknown location.The violent scenes forced shops and businesses in the area to close down, and it took the police two hours to clear the area of demonstrators.
The trial involved allegations against Mohammad Ali Taheri, founder of Erfan-e-Halgheh group who was arrested on May 4, 2011, by officials linked to Iran’s Revolutionary Guards and was held in Evin Prison.
He was later charged with 'spreading corruption on Earth', a catch-all indictment of political dissent which carries the death penalty.
His supporters have gathered on numerous occasions outside Tehran’s Evin prison chanting 'freedom of expression is our right'.
International rights groups have issued statements expressing concern about welfare of Mr Taheri, who is serving his sentence in solitary confinement and his repeated requests to be transferred to a cell shared with other inmates have been denied, leading him to go on hunger strike.