A video has been posted to youtube that appears to capture Iranian security forces firing automatic weapons at protesters. It was posted on July 20 and is described as happening in Tehran. But RFE/RL can't be certain of either its provenance or the date and location of the incident. The male and female onlookers who filmed it express horror as a protester appears to get shot in the leg by a small band of retreating uniformed and plainclothes security troops.
If authenticated, it would appear to refute officials' claims that Iran's security forces were not armed with guns or live ammunition.