Cape Town - A woman who bought vetkoek from a small business in Langa on the same day that three teens died after consuming it insists there was nothing wrong with it.Pia Ngoyi from Joe Slovo said, had the batch been poisoned, she wouldn't have been alive today."Look at me. I am fine," she said on Wednesday, while washing her clothes at a communal tap."I have been buying from them for a very long time. They make all their vetkoek from a big batch of dough – fresh, every day – so wouldn’t that mean I would have also felt sick? Something else must have happened here."The three friends - reportedly identified as Athule Makonzi, 15, Mzingisi Gobecimele, 17, and Khanyisa Mtamzeli, 17– died last Sunday.A fourth teen was hospitalised and has since been discharged.A number of residents pointed out the small business, operated from a shack in the heart of Joe Slovo, where the boys apparently bought the vetkoek.When approached for comment, a man and a woman denied they sold anything from their home.Locals, however, say they are indeed the sellers, describing their wares as "very nice and popular"."They won't say anything right now to anyone because people have been threatening them, saying they are the reason those children are dead," one neighbour said.They haven't been selling since the deaths, another confirmed.'Mixed other substances' in foodWestern Cape police spokesperson Sergeant Noloyiso Rwexana said authorities were still awaiting the autopsy results to determine the cause of death.Inquest dockets had been opened and are being investigated.Mayoral committee member for safety, security and social services JP Smith said police were awaiting a toxicology report and would activate the City of Cape Town's Environmental Health Division, should they need council to investigate the possible food poisoning aspect.Smith previously said the division had been in contact with police, who had indicated that it appeared that the children had "mixed other substances into their food".But Makonzi's sister, Pamela, denied this, saying it implied that the boys had put drugs or poison in the food themselves.She said her brother and his friends, whom she knew personally, would never had used any dangerous substances.Makonzi died within 30 minutes of showing signs of poisoning, Pamela said."He was at home when he said he felt like he was burning inside and started crying. We took him to the day hospital by car and he died soon after," she recalled.Pamela as well as the families of the remaining victims attended a memorial service held for the boys' classmates and loved ones at the Langa Indoor Sports Centre on Wednesday.