A man wanted for murdering the two toddlers found dead in Diepsloot could be of any nationality, Gauteng police said.
"Only after we arrest the man can we establish his true nationality," said Brigadier Neville Malila.
Police released an identikit of the man, who was initially thought to be Mozambican.
"We have conducted several interviews with members of the [Diepsloot] community and possible witnesses, since it was thought the man was Mozambican.
"The information we have gathered leans more to the suspect being from Swaziland or from KwaZulu-Natal, but at this stage he could be from anywhere," Malila said.
Police were offering a R100,000 reward for information leading to his arrest and successful prosecution.
"The suspect is in his early 30s, not older than 34, [of] slight build, 1.7m tall, light in complexion, and was wearing a wool hat," Lt-Col Lungelo Dlamini said.
"It is believed that he has different colour wool hats. He has a cut on the lower lip and a red ring on his left hand."
Four foreigners had been taken in for questioning.
The bodies of two-year-old Yonelisa Mali and her cousin Zandile Mali, three, were found in a public toilet cubicle in Diepsloot at 5am on Tuesday by a resident.
They were reported missing at the weekend.
Residents went on the rampage after the bodies were discovered.
Police said a team of detectives had been appointed to investigate the murders.