Iranian students chant anti-government slogans in Tehran

Iranian students chanted anti-government slogans at rallies for people killed during a recent wave of demonstrations, local and diaspora media reported Saturday, as groups protesting the clerical leadership faced off with others voicing support for the government.

Videos geolocated by AFP to at Tehran's top engineering university showed fights breaking out in a crowd as people shouted "bi sharaf", or "disgraceful" in Farsi.

Footage posted by the Persian-language TV channel Iran International, which is based outside the country, also showed a large crowd chanting anti-government slogans at Sharif University of Technology.

Iranians had reprised their protest slogans this week to mark the 40th day since the deaths of thousands of people as a wave of demonstrations was peaking on January 8 and 9, in line with Shiite mourning tradition.

They gathered again at several universities in the capital on Saturday, local media reported.

The unrest first broke out in December over prolonged financial strain, but exploded into mass anti-government demonstrations that were suppressed in a violent crackdown by security forces that rights groups say killed thousands.

The clerical authorities acknowledge more than 3,000 deaths, but say the violence was caused by "terrorist acts" fuelled by Iran's enemies.

The US-based Human Rights Activists News Agency (HRANA), however, has recorded more than 7,000 killings in the crackdown, the vast majority protesters, though the toll may be far higher.

Local news outlet Fars said that what was supposed to be a "silent and peaceful sit-in" of students commemorating those killed was disrupted by people chanting slogans including "death to the dictator" -- a reference to Iran's supreme leader.

A video posted by Fars showed a group chanting and waving Iranian flags facing off with a crowd wearing masks and being held back by men in suits.

Both groups were holding what appeared to be memorial photographs.

The demonstrations come as Iran's authorities are under pressure to make a deal on the country's nuclear programme with the United States, which has deployed forces within striking distance.

US President Donald Trump had threatened military action against Tehran during the protests over the crackdown by security forces.