Eighteen schoolchildren and four adults were injured when a bus crashed into several cars in Mayor's Walk in Pietermaritzburg on Tuesday, KwaZulu-Natal emergency services said.

"Four adults and 18 children were injured in the [accident]. The bus had been transporting schoolchildren," said Netcare 911's Jeff Wicks.

Earlier it was reported that 30 people were involved in the bus accident.

Wicks said it was alleged that the driver lost control of the bus and hit a person selling newspapers on the side of the road.

"All the wounded were treated at the scene? before they were transported to hospitals," said Wicks.