Cox, who ran in the heats for the American 4x400 metres team led by Sanya Richards, allegedly admitted to using the banned performance-enhancing drugs and agreed to the suspension imposed by the United States Anti-Doping Agency (USADA)  last month.

She was given the suspension after she allegedly admitted using steroids during 2001 and 2004 following an investigation started by information from the Bay Area Laboratory Co-Operative (BALCO) case, which has already claimed a number of high-profile casualties including Marion Jones and Britain's Dwain Chambers.

All her results during that period were also annulled.

The IOC have now set-up a disciplinary commission to investigate the case and could recommend that the American team is stripped of their medals.

That could see runners-up Russia promoted to gold, third placed Jamaica to silver and fourth-placed Britain to bronze.

Germany's Thomas Bach, the IOC vice-president, will lead the three man commission which will also include fellow IOC Executive Board members Denis Oswald, the Swiss President of the International Rowing Federation FISA, and Namibia's Frankie Fredericks, the former world 200 metres champion.

Bach said: "We have set up a disciplinary commission.

"We have to get more details and we will of course give her the opportunity to be heard."

The suspension could mean all members of the US 4x400m team, including Cox who ran in a qualifying round and finalists Monique Henderson, Monique Hennagan, Richards and Deedee Trotter, lose their medals.

Hennagan, who won gold in the 4x400m at the Sydney Games four years earlier but was stripped of it after Jones admitted to doping and has since appealed the decision, is now at risk of losing a second Olympic gold medal.

If Britain were promoted to third place then it would mean a first Olympic medal for veteran Donna Fraser who ran on the final alongside Catherine Murphy, Lee McConnell and Christine Ohuruogu, while Helen Karagounis, who ran in the qualifying round, would also benefit.

USADA claimed that Cox had admitted using steroids but she denies this.

She said: "I can sit and preach I am innocent and have never used steroids but proving my innocence was difficult without the money or the resources, going against a goliath like the United States Anti-Doping Agency.

"I fought as long as I could and tearfully signed the sanction ... but knowing in my heart and every fibre of my being I was innocent.

"If I did not sign the sanction, being banned [for life] from track and field would damage me more than the public scrutiny I am receiving now."

Contact the writer of this story at [email protected]


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