Pakistani powerlifter Naveed Ahmed Butt has been given a two-year ban after he tested positive for use of steroid last Thursday, two days before the opening ceremony.

Peter Van de Vliet is the medical and scientific director of the International Paralympic Committee or IPC.

He told reporters that despite the disappointment of a positive test, the incident highlighted the committee's efforts to run fair Games.

"The experience we have during previous games and over the past couple of years, I can without any doubt say that we had challenges in weight-lifting. And that means there are a significant number of athletes are subject to anti doping testing, both in competition and out of competition. "

Meanwhile, the IPC says that the re-run of a women's 5,000-meters competition is in the interest of fairness.

The crash of athletes' wheelchairs in Monday's women's 5,000m T-54 race led to six out of 11 runners unable to finish the race and three athletes injured.

Canada's Diane Roy finished first, followed by Britain's Shelly Woods and the United States' Amanda Mcgrory.

The result of the event was later withdrawn and the IPC's Jury of Appeal ordered a re-run of the race to be held on Friday.