Correctional Services spokesman Manelisi Wolela has denied allegations that student leader Mcebo Dla.
Charlize Theron's mother has taught her to never give too much away.
The Oscar-winning actress - who recently split from long-term partner Stuart Townsend - likes to keep some things to herself since she believes it improves the quality of her life.
She said: "There are little things that I want to hang on to for myself. I really do believe you can make certain choices in your life that give you the life you really do like.
"Maybe it was the way I was raised. My mom used to always say, 'There are certain things that are yours and you don't share that'.
"I know that so much of my life is out there already. Quality of life is important to me, and I don't know how much quality of life you can have if it's all out there for the world."
The SA-born Hollywood leading lady recently launched the Charlize Theron Africa Outreach Project and says she wanted to give something back to her native country.
She added to E! Online: "For me, going there when we launched, it was eye-opening that the things we take for granted are not the things that you can expect in rural communities in South Africa."