Arnold Pistorius, the uncle of Oscar, has denied suggested that the Paralympian was taking illegal performance-enhancing drugs.
Oscar was not using any drugs listed on the World Anti-Doping Agency banned substances, usage of which would ban him from competing in athletics competitions.
The IAAF will have records of every single drugs test that was undertaken in and out of competitions.
He has been tested on a number of occasions during the last couple of years and he has never failed a drug test to date.
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