President Cyril Ramaphosa has described the confrontation outside Brackenfell High School in Cape Town as deeply regrettable, calling for people to act with greater decorum.
On Monday, a violent confrontation broke out between a group of parents from the school and EFF members, who were protesting against alleged racism at the school.
Ramaphosa said in a statement on Tuesday allegations of racism levelled against Brackenfell High School needed to be urgently investigated.
The incident was sparked by a matric ball that was hosted privately, after the school had cancelled the annual event because of Covid-19.
Ramaphosa said: "At this most important and difficult time for matriculants, not only at Brackenfell High School but around the country, the spectacle of parents and protesters coming to blows at the school gate is deeply unfortunate.
"What happened today brings back hurtful memories of a past we should never seek to return to."
Ramaphosa called on all parties concerned to exercise restraint and to resolve their differences peacefully and through dialogue.
"We should not allow what has transpired at Brackenfell High School to be used by any groupings who want to cause racial polarisation," Ramaphosa said.
The Western Cape Education Department is investigating allegations that the school may be guilty of racism in its staffing practices. Currently, the school has two coloured teachers on its staff of 40 educators. No black teachers have reportedly been employed at the school since 1994.
Video footage showed angry members of the Brackenfell community and EFF protesters facing off. After a heated exchange, punches were thrown.
The EFF has said it intends returning to Brackenfell on Tuesday, to enforce a shutdown in the area. "They have pushed us, and they must be prepared to be pushed back harder," the party said in a statement.