Two of the Waterkloof Four appeared before the Correctional Supervision and Parole Board on Friday, pending a review of their parole, the correctional services department said.
"The decision will be taken on or before Friday next week after which an update will be given to the public through the media," department spokesperson Manelisi Wolela said in a statement.
"The investigation into the role probably played by correctional officials in the "WK2" is not concluded yet but we are closing in on the suspected culprits."
He said a further update would only be given at an "appropriate time" because of the "sensitivity and seriousness" of the case.
Convicted killers Frikkie du Preez and Christoff Becker were re-arrested on Sunday, four days after being released on parole. This was after a video, reportedly taken on a cellphone, was posted on YouTube. It shows Du Preez and Becker allegedly drinking alcohol, and using a cellphone in a jail cell in Pretoria's Kgosi Mampuru prison.
Bekker, Du Preez, Gert van Schalkwyk, and Reinach Tiedt were released last Tuesday after being jailed for beating a homeless man to death in Pretoria in 2001.
On Wednesday the department said Du Preez and Becker would remain in custody until the parole board has made a decision.
Correctional Services Minister Sibusiso Ndebele on Wednesday warned that "anarchy" at correctional centres would not be tolerated. "Any official, or offender, found guilty of any such offence will face the full might of the law," he said.
"As DCS, we will fight fraud and corruption with vigour."
According to the Public Service Commission Report for 2011/12 the DCS was the third best institution when it came to dealing with fraud and corruption, but more still needed to be done, Ndebele said.
The DCS said an average of 64 prisoners were granted parole in the country every day.
In addition to the country's 156 939 inmates, 65 931 were outside correctional centres living in their respective communities. Compliance with parole conditions currently stood at 98.4%. – Sapa