Three road carnages have claimed 19 lives within 24 hours in South Africa, authorities said on Saturday.

In the latest accident in Cape Town early Saturday, nine people died and 14 others injured when a construction vehicle overturned, the city traffic department said.

The victims were sitting on the back of the vehicle when the accident took place, the department said.

In another accident on Friday night, four people were killed in a head-on collision in Middleburg, Mpumalanga Province, provincial spokesperson Moeti Mmusi said.

Earlier on Friday, six people were killed and eight others injured when a truck they were travelling in lost control and collided into two vehicles in KwaXimba, KwaZulu-Natal Province, according to the provincial transport department.

Police said investigations were underway to determine the causes of the accidents.

Authorities urged motorists to use the road cautiously and follow traffic rules to avoid the loss of lives, particularly during the Heritage Day, a public holiday which falls on September 24.

Road carnage is a daily phenomenon, particularly during holidays in South Africa, which is among the countries that have the highest road fatalities.

The country has about 700,000 crashes a year on average, according to the South African Road Traffic Management Corporation.