South African police fired rubber bullets, stun grenades and teargas at student protesters in Johannesburg on Tuesday as authorities tried to re-open the prestigious Wits University after weeks of demonstrations.

The university, along with many campuses across South Africa, has been closed for at least two weeks during protests over tuition fees, with violent clashes regularly erupting between students, police and private security guards.

‘There has been an attempt to disrupt lectures at Wits today,’ the university said in a statement.

‘Police are dispersing the protesting students as we speak, using teargas and stun grenades.’

University authorities had vowed to re-open the campus on Tuesday, with vice-chancellor Adam Habib warning of the ‘immense consequences of not finishing the academic year’.

He said most students wanted to return to lectures, adding that police and security staff would ensure teaching could go ahead and that mass protests would not be allowed.

‘The university wants to arrest us, instead of listening to us,’ said 21-year-old Patrick Shabalala, a third-year law student, as clashes continued outside Wits' Great Hall auditorium.

‘We are not criminals. We want to study and not end up paying endless student loans from the government. That is why we are striking.’

As police opened fire and protesters threw rocks, television footage showed several students and at least one police officer sustaining minor injuries.

- Nationwide unrest -

Campuses nationwide including the University of Cape Town, the University of KwaZulu-Natal and the University of Pretoria have all been hit by violence, arson and closures in recent weeks.

The wave of protests was triggered by a government announcement that universities would set their own fee increases but that next year's hikes could only be as high as eight percent.

‘The struggle continues, not only here at Wits but across the country,’ said Phelokazi Caluza, 19, a first-year chemical engineering student.

‘Students are angry at the government, the governments responds by unleashing cops on us.

‘Exams are around the corner but if we don't fight, we will be facing the same problems next year.’

Sporadic unrest has hit many South African universities over the past year, as students have protested against fee increases that they say force poorer, often black, pupils out of education.

Last year, students -- many of them so-called ‘born frees’ who grew up after apartheid -- staged a series of huge demonstrations which forced the government to abandon planned fee hikes for 2016.

‘We do not agree with those who say that universities should be shut down,’ President Jacob Zuma said Monday, while confirming that students from poorer families would be given further financial assistance.

‘The wanton destruction of university property that we have witnessed are shocking criminal acts,’ he added.

Funding for South Africa's universities has been stretched as the economy endures flat-lining growth and the government struggles with a 27 percent unemployment rate.

Student activism played a central role in the fight against apartheid, with the massacre of pupils by white police officers in 1976 seen as a key date in the country's tumultuous history.