Other occupants of the vehicle sustained serious injuries.
Preliminary findings indicate that the vehicle hit a cow and went over a bridge plunging into a river, killing ten school pupils and the driver.
The children from Okhombe Primary School were returning from an event at Matiwane Primary School.
Rescue efforts saved six children. The bodies of six drowned children were initially retrieved. Three more bodies, as well as that of the driver, were later recovered by rescue divers.
Horror crashes in South Africa
In other separate incidents, a Toyota Avanza and Ford delivery vehicle collided head on resulting in the loss of six lives on the N2 between Mthatha and Dutywa.
The Road Traffic Management Corporation (RTMC) investigation is looking into a case of culpable homicide following a multi-vehicle pile-up on September 15, 2012, at Bora between East London and Port Alfred, Eastern Cape.
Two vehicles collided head-on followed by others crashing into them. Three sedans and two light delivery vehicles were involved. Four people were killed and six seriously injured.
Transport minister Ben Martins said: "We are terribly shocked and saddened at the news of these horrific incidents. The loss of such innocent lives on our roads is completely unnecessary.
We wish to convey our sincere condolences to the families of the deceased and wish those injured a speedy recovery."