A charge of rape would be added to the charge sheet of two men arrested in connection with the murder of a family of four in Middelburg last week, Mpumalanga police said on Tuesday.
Inspector Leonard Hlathi said investigations had revealed that the eight-year-old daughter had been raped before she was murdered.
Blood tests would be done on the two men to determine which one perpetrated the rape.
One of the men had already confessed to the murders and had pointed out the other one as his accomplice.
Hlathi said if the rapist was identified through the blood tests, he would be charged with rape. The other man would be charged as an accomplice to the rape.
The murder in the Mhluzi suburb of Middelburg was discovered when a neighbour of the family knocked on the door on Friday afternoon. She was told by a three-year-old boy, who survived the attack, that his mother "did not want to wake up".
She asked him to pull away the curtain and saw a woman hanging by the neck from the roof. Her hands had been tied behind her back using electrical cord.
The police found the body of a 30-year-old man with his hands tied behind his back. The body of the eight-year-old child was found in a bathroom and a six-year year old was found in a bedroom. Their hands were bound too.
The toddler was asleep at the time of his family being attacked and had spent four days in the house with the bodies of his parents and siblings.
Johannes Eugene Mahlangu, 33, and Johannes Fani Mtsweni, 31, were arrested on Sunday in connection with the murders.
They appeared in the Middelburg magistrate's court on Tuesday.
Hlathi said the family were allegedly murdered because of a belief in the community that they had won the Lotto.
This was, however, not true, he said.
Mahlangu and Mtsweni will appear in court again on June 14 for a bail application. - Sapa