Protests against Mahsa Amini's death rock Tehran university

Iranian students have clashed with security forces at a top Tehran university amid the wave of unrest sparked by the death of a young woman in the custody of the country's morality police, state media and rights groups have said.

Public anger has flared since authorities announced on September 16 the death of 22-year-old Mahsa Amini, who had been held for allegedly wearing a hijab headscarf in an improper way.

Concern grew over violence at Sharif University of Technology overnight where riot police confronted hundreds of students, using tear gas and paintball and carrying weapons that shoot non-lethal steel pellets, local media reported on Monday.

"Woman, life, liberty," students shouted, as well as "students prefer death to humiliation", the Iranian Mehr news agency reported, adding that the country's science minister later came to speak to the students in an effort to calm the situation.

The Oslo-based group Iran Human Rights posted video apparently showing Iranian police on motorcycles pursuing running students in an underground car park and, in a separate clip, taking away detainees whose heads were covered in black cloth bags.

READ MORE: Scores killed in Iran's Mahsa Amini protests – rights group

Concerns grow

In other footage, shooting and screaming can be heard as large numbers of people run down a street at night, in footage AFP news agency has not independently verified.

"Security forces have attacked Sharif University in Tehran tonight. Shooting can be heard," IHR said in a Twitter message on Sunday.

In another video clip, a crowd of people can be heard chanting: "Don't be afraid! Don't be afraid! We are all together!" IHR said the footage was taken at Shariati metro station in the capital Tehran on Sunday.

The New York-based group Centre for Human Rights in Iran said it was "extremely concerned by videos coming out of Sharif University and Tehran today showing violent repression of protests + detainees being hauled away with their heads completely covered in fabric".

Mehr news agency said that "Sharif University of Technology announced that due to recent events and the need to protect students...all classes will be held virtually from Monday".

The death of Amini has sparked Iran's biggest wave of protests in almost three years.

Since the unrest started on September 16, dozens of protesters have been killed and more than a thousand arrested. Members of the security forces have been among those killed.

READ MORE: Iran: Second Revolutionary Guards colonel killed in clashes