A leading university in South Africa has closed for the rest of the week because of violence by protesters demanding free education.

The University of the Witwatersrand in Johannesburg says it is identifying those who participated in campus violence on Tuesday and will take action against them.

Protesters had thrown stones at security guards outside a main campus building. Some guards threw projectiles back at the students.

The demonstrators were reacting to a government announcement that universities can increase fees by up to 8 percent next year. The government has promised to pay about $180 million to cover the costs of poor students.

Students have staged protests on some other South African campuses. Classes were suspended Wednesday at the University of Cape Town because of security concerns.