Garrith Jamieson of ALS Paramedics said four trucks had been involved in a collision with either two or three cars.
The trucks had caught alight.
Jamieson said one of the truck drivers had sustained serious injuries. He was being stabilised on the scene and would be rushed to hospital.
“The N3 Durban-bound is currently closed at the Shongweni off-ramp and motorists are urged to use alternative routes,” said Jamieson.
The cause of the crash was not immediately clear.
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