Angry residents in Naledi, Soweto, gathered outside a spaza shop on Tuesday after the deaths of two young children.
Neo Khang, aged four, and Leo Jele, six, died on Sunday.
The cause of their deaths is yet to be ascertained.
The two children, with Katlego Mbatha and Olwethu Zikhali, allegedly ate biscuits purchased at their local shop, a street away from their homes, before they became ill.
Mbatha and Zikhali are receiving treatment in hospital. One child is in a critical state, according to the family and community.
Khang died on the way to the local clinic. He and Mbatha are relatives from the same house. She was the only girl among the four children.
Police officers stood guard in front of the closed shop on Tuesday to ensure the premises are not breached, especially after officers returned with the owner from the police station earlier in the day.
Operation Dudula members joined residents at the shop. Activist Nhlanhla Lux kept a low profile.
Ward councillor Lazarus Mmota, who visited some of the families on Tuesday, said the community was saddened by what had happened and the important thing was to ensure calm was maintained during the investigation.
While he alluded to suspicions that the deaths could be due to something the boys consumed, he insisted the outcome of autopsies would provide clarity.
“This is very sad, especially if you check the ages. But let's wait for the postmortem results before we speculate it is biscuits,” he said.
A meeting will be held with community members on Tuesday.
TimesLIVE
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