South African police have set off stun grenades and thrown tear gas at stone-throwing students from a leading university who were demonstrating for free education.
The chaos in the streets around the University of the Witwatersrand in Johannesburg followed violent protests on the campus yesterday that forced the university's closure for the rest of the week.
Several students were injured in the latest unrest, South African media reported.
The University of the Witwatersrand said it is identifying those who participated in yesterday's campus violence and will take action against them.
Protesters threw stones at security guards outside a main campus building, smashing some windows. Some guards threw projectiles back at the students.
Classes were also suspended Wednesday at the University of Cape Town because of security concerns.
Stellenbosch University said it obtained a court order requiring 30 protesters to leave a campus building they had occupied, or face removal by the police.
The demonstrators have been reacting to a government announcement that universities can increase fees by up to 8% next year.
The government made a concession to student protesters last year, agreeing to freeze fee increases for this year.
The government has promised to pay about $180m (€161.3m) to cover the costs of poor students.
Blade Nzimande, the South African education minister, has condemned violent student protests, saying the government has "gone a long way" to financially support poor students and that students with resources should pay fees to help cover rising university costs.