Two days after the body of a girl and boy were found in a veld in Soweto, their decomposing remains have not yet been identified, Gauteng police said on Wednesday.
A passer-by discovered the bodies - buried in a single shallow grave - behind Slovoville cemetery on Monday.
The boy is estimated to be about 11 and the girl 10.
They had been blindfolded and their hands were tied, police spokesperson Captain Kay Makhubele said.
"At this stage, no cases of missing children were reported at any of the police stations within the Soweto West cluster. Therefore, the possibility that the children could have been reported missing outside of the cluster cannot be ruled out," he said.
Police have appealed to anyone who has further information about the missing children to contact authorities.
"This will assist with the identification of the victims and ultimately, the apprehension of the suspects.
"Meanwhile, in line with the national instruction to prioritise cases against women and children, police will leave no stone unturned to ensure that the perpetrators of this heinous crime against the children are found [and] face the full might of the law."
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