The deaths of 34 miners during the Marikana massacre in 2012 will be commemorated by the Association of Mineworkers and Construction Union (Amcu) on Wednesday at the hillside where the massacre occurred.
Police shot and killed the miners on August 16, 2012, in an apparent attempt to disperse striking Lonmin miners. Miners demanded that their salaries be nearly tripled to R12 500 a month.
It is believed to be the most lethal use of force by South African police since the dawn of democracy.
Ten people, including two police officers and two Lonmin security guards, were killed in the preceding week.
On Thursday, IOL reported that AMCU president Joseph Mathunjwa barred ANC presidential hopeful Cyril Ramaphosa from attending the commemoration, saying Ramaphosa's interest in Marikana was purely for campaigning purposes.
At the start of the Lonmin strike action, Ramaphosa sent an email to then minister of police Nathi Mthethwa, requesting additional police deployment to the area to "protect life and property".
Ramaphosa was a non-executive director of Lonmin at the time.
The Farlam Commission of Inquiry, instituted by President Jacob Zuma to investigate the massacre, cleared Ramaphosa from any wrong doing.
The commission also called on the South African Police Service (SAPS) to remove all automatic military assault rifles such as R5 rifles from Public Order Police's arsenal; demilitarised and professionalised the police service and record and save all radio communications during strike action.
R5 rifles were predominantly used in the killing of the 34 miners.
A subsequent commission recommended that then police-commissioner Riah Phiyega was not fit to hold office.
She was suspended on October 2015 and her term as police-commissioner came to a close in June 2017.