Metrorail said more people are still believed to be trapped inside the two trains which collided in Mountain View, northeast of Pretoria, on Tuesday.
Three people were killed and hundreds more were injured.
Spokesperson Lillian Mofokeng said they are prioritising the rescue mission to get to the trapped passengers.
"For now we don't have the full details of what caused the accident," she said.
Mofokeng said both trains, carrying more than 800 passengers, were from Mabopane station heading towards Pretoria station.
"Unfortunately one was stationary on the platform when the other one hit it at the back," she said.
More than 300 people have sustained minor injuries.
Fifty ambulances were at the scene and three helicopters assisted with getting critically injured patients to hospitals.
Tshwane Mayor Solly Msimanga said he has always raised concerns about the infrastructure of railway lines and their outdated resources.
Msimanga said that he plans to meet with the families of the deceased.
- African News Agency (ANA)
(Pic:ER24)
