Correctional Services spokesman Manelisi Wolela has denied allegations that student leader Mcebo Dla.
Two Pretoria men drowned when their boat capsized in the middle of a dam in Mpumalanga yesterday.
The men, from Soshanguve, were aged 48 and 22. They cannot be named until their families have been informed, police said.
The men were fishing when their boat tipped over in the Mkhombo Dam Nature Reserve in the KwaMhlanga area at about 7am.
A man who witnessed the incident said he was too traumatised to comment.
Police said that strong wind, a leaking or overloaded boat, or even ignorance could have resulted in the accident.
Constable Vusi Ntuli said: "It is not clear what caused the boat to tip over but investigations are continuing."
He said an inquest had been opened at the Vaalbank police station.
The men were not wearing life-jackets.
Mkhombo Dam is one of deepest and largest bodies of fresh water in Mpumalanga. It measures about 9km in length and is 3km wide, with a circumference of 25km.
At the time of going to print yesterday, police divers from Ermelo were still searching for the victims' bodies.