Small protests broke out around the University of Tehran on Saturday, local media reported, in a third day of demonstrations sparked by anger over Iran's economic problems.
A video shared on social media appeared to show students scuffling with police in downtown Tehran near the city's university and chanting slogans against the regime.
The conservative-linked Fars news agency put the number of protesters at "between 50 and 70" and said riot police had been dispatched to the scene.
"Unlike other protests in various cities which were against the economic situation and high prices, the one in front of the University of Tehran was political," Fars said.
The students repeated a popular chant of "Not Gaza, not Lebanon, my life for Iran" -- an expression of anger over claims the government is focusing more on regional issues than problems at home.
The protests were far smaller than those seen in other cities on Thursday and Friday, which began with a demonstration against high living costs in second city Mashhad.