Some 40 people were injured after a truck carrying cooking oil overturned on the N1 north freeway near the 14th Avenue turn-off and caused a pile-up of up to 18 vehicles on Sunday, said Netcare 911.

Spokesperson Nick Dollman said of the 40 injured, 12 were taken to surrounding hospitals for further treatment.

"Several patients sustained serious injuries but there were no critical patients. At this stage there does not seem to have been any fatalities," he said.

Dollman added that paramedics found two vehicles including an Audi and a bakkie almost completely under the truck.

"Many motorists had to climb out of their windows as they could not open their doors because of how the cars had been compacted together," he said.

The accident happened around 6.30pm after a large truck with two trailers carrying cooking oil overturned and took up the entire width of the freeway, Dollman said.

It was suspected that a few thousand litres of oil was spilt on the highway and that the accident could take several hours to clear.

"Unfortunately many civilians heard about the massive oil spill and risked their lives by running across the opposite side of the highway to try and salvage some of the unbroken bottles of oil," Dollman said.

Senior Superintendent Wayne Minnaar earlier warned motorists to avoid the route as traffic was badly backed up.

Sapa

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