"We don't regard it as a matter deserving of a comment from the presidency," said spokesman Mac Maharaj, who initially said comment should be sought from the African National Congress, as it was an ANC event.

"Nothing happened there yesterday that warrants a comment from the presidency."

Five people were detained and released on a warning on Tuesday after violence erupted at a hall in Thohoyandou, where Zuma was delivering a lecture about the legacy of former president Nelson Mandela.

Zuma, who is also ANC president, was in the province as part of the ruling party's programme to mark its centenary.

Media reports ahead of the event had predicted problems given the party's recent expulsion of ANC Youth League president Julius Malema, who hails from Limpopo.

Provincial police spokesman Brigadier Hangwani Mulaudzi said a group of people began blocking roads in the vicinity of the Holy Worship Church hall on Tuesday afternoon ahead of Zuma's arrival. About 300 people converged outside the church hall and carried banners with Malema's picture, singing: "Zuma is troubling us".

They became involved in a fight with security guards when they entered the hall at 4pm.

"Those people are anti-Zuma and came inside the venue and started singing anti-Zuma songs. Then the ANC security inside the hall contained them and assaulted them," said Mulaudzi, adding that the police were called in to defuse the situation.

Zuma began speaking after 5pm. Violence continued outside the hall during his address.

"They continued to cause a disruption. Even when President Zuma started and was busy with the lecture, they were pelting police with stones," said Mulaudzi.

Police used a water canon to bring the situation under control.

Zuma's lecture touched on the history of the youth league in Mandela's time. Mandela and his friend Oliver Tambo were founding members of the league in 1944.

"The ANC youth was impatient with the leadership of the time, whom they felt were too gentlemanly in their approach to the struggle," said Zuma. Three ANC spokespeople contacted were not immediately available for comment on Wednesday.