Police spokeswoman Eveline Hardaker said on Monday that the woman's identity was still unknown and that her head was still missing.
Hardaker also urged people with missing family members to contact police. The Ministry of Women, Children and Persons with Disabilities earlier urged the public to help police search for the missing head.
Spokesman Sibani Mngadi said the ministry condemned acts of violence against women and girls and described the murder as one of "grave concern".
He also called for the maximum sentence to be handed to those found guilty of the crime.
Police said no arrests had been made yet.
The burning suitcase containing the torso was discovered by a passer-by on a stream bank in Sunnyside on Saturday afternoon.
The body was found dressed in a white and orange T-shirt.
A day later, the dismembered arms and legs of the victim were found wrapped in plastic in a rubbish bin.
Anyone with information can contact Inspector Zilonkulu on
082-719-8373.
Sapa
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