4:20 p.m. More reported attacks by security forces: Claims that protesters have been badly beaten in Valiasr Square and along Valiasr Avenue and Rasht Avenue.

On Twitter, @madyar is reporting that 200-300 security forces have gathered in Laleh Park to stop any protesters from gathering there.

4:15 p.m. First reports of violence in Tehran: We’re hearing that clashes have occurred between protesters and security forces near 16 Azar Ave and under College Bridge. Protesters have been beaten.

Cell phone service in Enghelab Square and adjacent streets in Tehran has been blocked.