Johannesburg - Members of the uMkhonto weSizwe Military Veterans' Association (MKMVA) gathered outside the ANC's Luthuli House headquarters in Johannesburg on Friday morning, ahead of a march by the Democratic Alliance.
Dressed in camouflage, the MKMVA members stomped their feet as they sang.
Thousands of African National Congress supporters marched to the nearby Beyers Naude Square, holding the party flag, while others carried sticks, golf clubs and sjamboks.
A source with knowledge of security operations told News24 that people stationed on the Luthuli House rooftop were police snipers.
MKMVA national executive committee member Mabel Rweqane said the association had mobilised to defend the party's headquarters.
"We are here to defend our HQ - the HQ of the African National Congress - from any harm that may arise from the march that is coming led by the DA. Most of the marches have been organised in the name of [peace, but] at the end of the day they end up violent," she told News24.
"Stoning people, stoning cars, stoning buildings, looting and all that. We don't want that to happen on these premises."
When asked by News24 about claims that the ANC was instigating violence with the show of force outside Luthuli House, she asked: "Why must we not be here? We are here as MK, we are here to defend the ANC."
'Defend the revolution'
The ANC denied being responsible for gathering supporters outside its headquarters to protect Luthuli House.
Two stages, mounted on the backs of trucks, were also set up at Beyers Naude Square, which is a short distance away from the headquarters.
Provincial leaders from Mpumalanga, Free State and KwaZulu-Natal were also spotted in the crowd.
"We are here to defend our revolution," Mpumalanga deputy chairperson Violet Siwela told News24.
ANC head of communications Khusela Sangoni said the national office had nothing to do with the demonstrations.
"Members of the ANC started descending this morning. Then the leadership would have felt, let's take out one of our trucks. Let's engage them, appeal to them so they can exercise maximum restraint and discipline," Sangoni said.
"We do not want a situation where people are roaming the streets - this way we get to contain them," Sangoni said.
Call for an ethical leader
DA leader Mmusi Maimane is expected to lead the party's march in Johannesburg on Friday, as part of the nationwide shutdown aimed at supporting calls for President Jacob Zuma's head.
Thousands of DA supporters gathered at the Westgate transport hub, clad in their blue T-shirts.
They held placards that read "Fire Zuma", while one banner read "Zuma must fall. A nation divided will never stand together".
DA spokesperson Phumzile van Damme said the party's "simple" message was that it wanted an ethical leader for SA.
Van Damme has also called on ANC MPs to support the party on the forthcoming motion of no confidence against Zuma in Parliament.
"We want a better South Africa and we are here today to give space to all to join us today as we march for change," she said.
'It's obvious, Zuma must go'
Joseph Sethabela from Sebokeng said coming to the march was better that sitting at home and waiting for change.
"It's obvious man, Zuma must go man. I'm not doing this for me. I'm doing this for my children and their future," he said.
Terry Shead brought his family to the DA's march.
"If I don't do anything I know I'm not serving my country. And serving my country means I won't live with corruption," Shead said.
There were reports about demonstrations along Rivonia, Malibongwe and Beyers Naude roads in Johannesburg.
Meanwhile, other marches against Zuma are expected to be held across the country, including one at Church Square in Pretoria. Protesters are expected to make their way from the square to the Union Buildings later on Friday.
The nationwide action was prompted by Zuma's Cabinet reshuffle last week. He appointed 10 new ministers and 10 new deputy ministers. Former finance minister Pravin Gordhan and his deputy Mcebisi Jonas were among those axed.