Desmond Tutu made an appearance at protests in Cape Town
It's believed that up to 50,000 people have turned out to protest against President Jacob Zouma across South Africa.
Protesters are demanding that he quits after a cabinet reshuffle triggered the latest crisis of his presidency.
Zuma sacked Finance Minister Pravin Gordhan last Thursday, which outraged allies and opponents alike and undermined his authority causing rifts in the ruling African National Congress (ANC).
Concerns have also been raised about the struggling economy and government corruption. Zuma still retains the backing of powerful factions within the ruling ANC party.
Divisions over his conduct are growing however in the party, as its legacy of having a leading role in the fight against white minority rule, has eroded during his tenure.
Nobel laureate and anti-apartheid leader Desmond Tutu, made a rare appearance to support the protests on Friday
His foundation posted a tweet in his name saying "We will pray for the downfall of a government that misrepresents us."
In Johannesburg, police fired rubber bullets to disperse about 100 ruling party members who were making their way toward protesters, according to the African News Agency.
Separately, ruling party members assaulted several protesters participating in a march organized by the Democratic Alliance, South Africa's biggest opposition group.
Having faced protests in the past, analysts have doubted that the most recent rallies are likely to shake the president.
Members in parliament said they would vote against a motion of no confidence in Zuma on April 18th, a key rallying call for the marchers on Friday.