A spokesman from the Department of Correctional Services told the Times newspaper that Oscar Pistorius was allegedly involved in an altercation.
It was “over the use of a public phone in the special care unit” where both offenders are detained, he said.
Oscar Pistorius had been taken for a medical check-up after the dispute and was found only to have a bruise, he added.
“As standard operating procedure regarding cases of alleged assaults, DCS has launched an internal investigation into the matter to establish the facts and to ensure that appropriate action is taken as incidents of assault are not allowed.”
Pistorius, whose lower legs were amputated because of a congenital defect, soared to international fame after becoming the first double amputee to compete in the 2012 Olympic Games.
In 2015, in a case that gripped the world, Pistorius was found guilty of the Valentine’s Day murder of his girlfriend, the model Reeva Steenkamp.
The South African sprinter, known as the ‘Blade Runner’ for his prosthetics, maintains he believed Ms Steenkamp was an intruder when he shot her through the bathroom door.
He is serving a 13-year sentence.
