Johannesburg - Three children were burnt to death in a shack fire in Soweto in the early hours of Wednesday morning, police say. The bodies of the children – aged 6, 3 and 1 - were burnt beyond recognition, said Captain Mpande Khoza.Their parents were taken to Chris Hani Baragwanath Hospital, where they were treated for burn wounds and smoke inhalation after they managed to escape from the burning shack in Doornkop Block 2.They have since been released.It is not yet clear what caused the blaze."Both parents were with their kids inside the shack when the fire started. They managed to escape but they could not manage to save their three children," he said.An inquest docket was opened for investigation."[Investigating officers] are still waiting for full details about the cause of the fire from the parents of the deceased children. The police are also waiting for a full report from the crime scene expert," Khoza said.