At least 21 people have been killed and several others severely injured following a head-on collision between two minibus taxis and a third vehicle on a major highway in South Africa, authorities said on Monday, The Independent reports.

The incident occurred on Sunday night in the Western Cape Province between Prince Albert and Leeu-Gamka, roughly 380 kilometers east of Cape Town, according to the Road Traffic Management Corporation.

The agency noted that the death toll "may change as emergency services and authorities in the Western Cape continue their assessment of the scene."

Three of the casualties were rushed to hospital but were pronounced dead upon arrival, police said.