Witnesses said a clash erupted between a taxi driver and agents of the state security police in Tajrish Sq. in Tehran on Sunday Dec 28th where this taxi driver became angry and punished the agent after he was harassed by the police. 
The incident started when this suppressive state security man tried to arrest a little girl who was making living off a weight scale she had. When the girl saw the police coming, she grabbed her equipment and ran away, but tripped and fell over a pavement. The state police tried to grab the girl and take her to the station while confiscating her scale. A taxi driver who was waiting for his passenger saw the incident and went to help that young little lady. Minutes later they got in to a physical fight and attracted the attention of other people in the neighborhood. After a crowed was gathered around the two, the little girl escaped and the suppressive state security man saw that crowed so he left the scene too.