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The cause of the accident is under investigation

The crash occurred just north of Pretoria

Johannesburg, South Africa CNN  — 

At least 18 schoolchildren were killed when a minibus and a truck collided north of the South African capital of Pretoria on Friday, emergency services authorities said.

The driver of the minibus was also killed, emergency services spokesman Russel Meiring told CNN.

Medical personnel treated several children at the scene.

The minibus burst into flames after the collision. The cause of the accident is still under investigation.