Eleven South African minibus taxi drivers were shot dead and four injured when unknown gunmen opened fire on their vehicle in KwaZulu-Natal province, police said.

The national commissioner of police, Khehla Sitole, said the men were travelling back to Johannesburg from a colleague’s funeral on Saturday night when they were ambushed.

“Preliminary reports indicate that the 11 were among 17 people coming from a funeral ... Four victims were critically injured and taken to hospital while two survived unscathed,” he said.

Police launched a manhunt to find those responsible.

“We will await for the investigation to advance before speculating on a motive,” said Sitole.

Private minibuses provide essential transport for millions of South Africans, but violence is common between rival taxi groups as profitable routes are hotly contested.