Train crash: Driver fighting for her life
Emergency officials say the female train driver may have sustained head and spinal injuries.
A Tshwane Business Express train crashed into the back of a stationary Metro Plus train just after 7am.
WATCH: Metrorail trains collide
Transport Minister Dipuo Peters, who visited the crash site, said this wasn't a usual occurrence.
"Prasa [the Passenger Rail Agency of South Africa] has a good track record. For us it is a shock to our own system because we have never seen this type of accident in the last few years."
The minister said rail safety remained a top priority and everything would be done to ensure a thorough investigation was conducted.
Peters says, "This accident shouldn't say to people that they shouldn't use trains because our train systems are safe."
Prasa's Lucky Montana says they will offer assistance to all the victims.
"We will pay the medical costs of all the people who were on board. That is our responsibility."
Wreckages of two trains that collided at Denver station in Johannesburg on 28 April 2015. Picture: Louise McAuliffe/EWN.
Johannesburg Emergency Service spokesperson Robert Mulaudzi says they spent some time freeing the driver.
"We suspect she might have sustained some spine and heard injuries because of the position she was in. She was airlifted to Milpark [Hospital] for further medical care."
At least 240 people were injured and taken to nearby hospitals.
At least 80 patients have been discharged.
LISTEN: Railway Safety Regulator's Babalwa Mpendu: 'Investigators concluded the investigation'
ER24's Russell Meiring described the scene upon arrival.
"ER24 paramedics as well as other services arrived on the scene and found the two wrecked trains over the entire train yard. On inspection, paramedics found a multitude of injured patients lying all around the scene. One woman had remained trapped inside the train between a wall and required advanced life support."
Public transport has come into sharp focus following this morning's crash and another incident on Friday involving Metrobus in which three people were killed.