Nelson Mandela intervened to stop a violent confrontation Saturday after police fired rubber bullets and tear gas at hundreds of black youths.

The African National Congress leader rushed to Elkah Stadium in the black township of Soweto after riot police blocked some 700 youths who tried to march to a nearby police station. Five people were injured by rubber bullets, but marchers refused to disperse.Police said they fired because the marchers did not have a permit to stage a demonstration and ignored orders to disperse. The marchers had been taking part in a rally to demand release of political prisoners.

Mandela protested to police at the scene and demanded they pull back. He then met with police Maj. Gen. Johann Swart at the police station.

Police said they agreed to release 32 marchers who had been arrested.

"I was concerned with defusing the situation, getting the people behind bars released," Mandela said later at an airport press conference before leaving for a visit to India, Japan and Australia.

Witnesses said Mandela's intervention calmed the situation.