Metrorail's preliminary report into the train crash that killed one person and left 243 injured show that driver skipped a red signal.
The two trains collided between Kaalfontein and Tembisa yesterday, while using the same rail but travelling in opposite directions.
Metrorail has set up a board of inquiry to investigate the cause of the accident.
Railway Safety Regulator of South Africa spokesperson, Babalwa Mpendu, says they are still waiting for the full report to know whether there were any other factors at play.
We know for sure that human factors have been the biggest contributor to the high number of incidents. There is a number of increase over the years due to human factors.— Babalwa Mpendu, Railway Safety Regulator of South Africa spokesperson
Mpendu says the preliminary report will be out on Tuesday.
WATCH: (Note: Video may upset sensitive viewers.)One dead, 243 injured in Tembisa train collision