Johannesburg - Correctional services national commissioner, Xoliswa Sibeko, and the department's acting chief financial officer, Nandi Mareka, have been placed on precautionary suspension with immediate effect, the department said on Monday.
"The reason for placement on precautionary suspension is to ensure the investigation into the renting of accommodation for senior executives, amongst others, is not interfered with," said department spokesperson Manelisi Wolela.
"It is important to note that there is no finding on these matters and therefore there is no judgement," he added.
Wolela declined to elaborate on the investigation. He said both Correctional Services Minister Nosiviwe Mapisa-Nqakula and the commissioner regarded the investigation as "serious".
According to a statement, Mapisa-Nqakula announced the establishment of an investigative team at a special executive management committee meeting on Monday.
The Public Service Commission team would investigate Sibeko's conduct.
Recent media reports said that Sibeko and her Gauteng counterpart were renting properties costing the taxpayer around R35 000 per month.
Rapport newspaper said the rentals were in the exclusive Woodhill area of Pretoria, and were being used while the official residences stood empty.
Democratic Alliance shadow minister of correctional services, James Selfe, welcomed the pair's precautionary suspension, saying the fact that the minister had taken action was "encouraging" but was "only the beginning of what needed to be done".
"The DCS [department of correctional services] desperately needs a turnaround strategy to lift it out of the morass of mismanagement that has characterised the last five years," Selfe said in a statement.