JOHANNESBURG (AP) — A truck and a school minibus were in collision in South Africa’s Gauteng province Monday, killing at least 13 children, authorities said.

Preliminary reports indicated at least 11 schoolchildren died at the scene, with two others succumbing to their injuries in the hospital.

The private vehicle was transporting students to various primary schools and high schools in the southwest of Johannesburg on Monday when the incident occurred around 7 a.m., according to authorities.

Witnesses said the minibus carrying the children was overtaking stationary vehicles when it hit the truck in a head-on collision. Police said the incident is being investigated and the truck driver will be questioned.

Provincial education department minister Matome Chiloane told reporters that the driver of the school bus would also be investigated for possibly driving recklessly.

Gauteng Emergency Services transported five patients to the Sebokeng Hospital, while two others were taken to Kopanong Hospital for further medical care. The bus driver also suffered injuries and was among those taken to the hospital.

Parents were seen weeping uncontrollably at the scene of the accident, while emergency services were picking up books and stationery.

President Cyril Ramaphosa expressed his sadness at the loss of life, saying national and provincial authorities would provide families and schools with the necessary psychosocial support.

“Our children are the nation’s most precious assets and we must do all we can — from observing the rules of the road to the quality of service providers,” said Ramaphosa.

The country’s minister of basic education, Siviwe Gwarube, said many accidents involving school transport are caused by driver error. She also called on the Department of Transport to make sure that vehicles entrusted with transporting schoolchildren are roadworthy.