Twenty men and six women were arrested in Braamfischerville on the West Rand in the early hours of Friday in connection with the necklacing of two men in the area on Tuesday, said police.
Captain Paula Nothnagel said the arrested residents - aged between 18 and 42 - were being questioned and might face charges of abduction, assault and two counts of murder.
Some fifty residents rampaged through the streets of Braamfischerville on Tuesday night looking for thieves who had broken into their houses and committed other crimes in the area.
Two suspects, brothers Tefo and Bashman Khoza, were found by the mob and dragged into the open veld where they were beaten before petrol-soaked car tyres were put round their necks and set alight.
Nothnagel said two residents had turned state witness and were in a place of safety. - Sapa