Traffic in both directions on the N1 in the vicinity of Pienaars River came to a standstill on Monday afternoon after a tanker collided with a bus.
The accident happened north of the Maubane toll gate between Hammanskraal and Bela Bela.
Nine people were apparently transported by ambulance away from the scene.
Footage shared by the Transit Assistance Bureau showed the tanker on fire with what appears to be a tautliner perpendicular to the highway.
This was still a developing story at 13:40 on March 24.
It's unclear to what extent the N1 supply route between Gauteng and South Africa’s border with Zimbabwe has been affected.