The South African government said five people have died in riots this week in and around the capital, Pretoria, though it reports progress in stabilising areas where violence has occurred.
The government said on Thursday that police have arrested 150 people on charges including public violence, theft and possession of unlicensed firearms and suspected stolen property.
Authorities say trouble persists in the districts of Mabopane and Soshanguve.
The violence started Monday because of discontent among some residents over the selection of the ruling party's mayoral candidate for Pretoria ahead of local elections on August 3. Crowds looted shops and burned vehicles in at least half a dozen areas.
Government spokesman Siphiwe Dlamini noted reports that some children were involved in crimes and appealed to parents to take care of their children.