Six suspected gang members, including a witch doctor, have been killed by a vigilante mob in South Africa after residents took the law into their own hands to beat widespread violence in their townships.

Police said some of the victims were burned alive and two were stoned to death when the group of 400 people set upon the men in two towns on the outskirts of Johannesburg.

One victim was a 61-year-old witch doctor, known locally as a Sangoma, who died when the mob burned down his home and set him alight in Khutsong.

The mob accused the traditional healer of hiding local criminals and working with the gangsters. He was reportedly killed in front of his family.

Two men aged between 20 and 24, who the police said belonged to a criminal group known as the Casanova Gang, were and also burnt to death during the attack.

Khutsong residents threw stones at police who were trying to calm the situation.

The vigilantes then moved on to the nearby town of Carletonville where they stoned to death two more suspected gang members.

There have been no arrests but police have condemned the actions of the mob as "unjustifiable".

"Vigilante acts are never justified, and the perpetrators of these crimes will feel the full force of the law,'' police minister Nathi Mthethwa said.

The attack took place after residents met to discuss what could be done about the criminals living in the area. Vigilante attacks are common in South Africa townships with residents complaining that police do not adequately tackle criminal violence themselves.

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