The statement by President Cyril Ramaphosa's office says a minibus, truck and delivery vehicle crashed on Friday on a major highway between Mookgophong and Kranskop.
Ramaphosa says that "It is all the more worrying considering that barely a month ago 11 people lost their lives on the same stretch of road when a bus overturned."
Neither the presidency nor emergency responder ER24 released details on what caused the accident.
South Africa's Road Traffic Management Corporation says 14,050 traffic deaths were recorded in 2017 alone.
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