Egyptian security forces have attacked student protesters at universities across the country, tightening their crackdown on student activism.

Clashes erupted on different university campuses following assaults by security forces on the demonstrators demanding the release of fellow students arrested in previous anti-government protests.

Security forces arrested five people at Cairo University, where the Students Against the Coup movement was holding a protest march to censure the deployment of forces at the entrance to the institution.

At Al-Azhar University, the security forces fired tear gas at protesters in a bid to disperse them, while skirmishes broke out at Ain Shams University in the east of the capital and also at Helwan University in a southern district of the city.

Students in the northern city of Alexandria, meanwhile, set fire to the entrance to a college to protest against the detention of one of their classmates.

Mohamed Atef, the president of the student union at Al-Azhar University, said the police had stormed his family home in Assiut on Monday looking for him and had nabbed his brother.

More than 90 students have been arrested in Egypt since Friday, according to the Association for Freedom of Thought and Expression, amid efforts by the authorities to squash a renewed wave of opposition protests around the country.

Egypt’s university campuses have witnessed regular protest rallies since the military ouster of the country’s first democratically-elected President Mohamed Morsi in July 2013.

More than 1,000 students have been arrested since the government launched a crackdown on pro-Morsi supporters, many of whom have been given harsh jail terms in mass trials. Officials also say more than 500 students were expelled or suspended for “rioting.”