Four Olympic show jumpers and one dressage rider face the International Equestrian Federation (FEI) disciplinary panel next week after second samples from all five horses proved positive for a prohibited substance.

The second samples of all four show jumpers — Bernardo Alves of Brazil and Chupa Chup, German rider Christian Ahlmann and Cöster, Denis Lynch of Ireland (pictured) and Lantinus and Norway’s Tony Andre Hansen and Camiro — all tested positive for the prohibited chilli derivative, capsaicin.

They are now joined by American dressage rider Courtney King and Mythilus, who have tested positive for felbinac, a banned anti-inflamatory drug.

An FEI spokesman explained the late announcement of Ms King’s suspension saying: “Given that the dressage events of the 2008 Olympic Games ended on 19 August it was decided to wait until the confirmatory B analysis prior to any public announcement of the findings.

“The FEI has now received confirmation of the initial finding from the analysis of the B sample.”

Evidence and written submissions have been requested from each rider, and a three-member panel of the FEI Tribunal has been appointed. Hearings will be held on 5, 6 and 7 September in Lausanne.

The panel will then take a decision as to the applicable sanction if any and the Olympic competition results will be amended if necessary.

The FEI said the final decisions shall be announced before the end of the first week in October, provided the hearings can be held as scheduled.

Horse Sport Ireland confirmed that they had been informed by Denis Lynch that he would be taking up his right to a hearing and that he intended to make himself available on any of the dates proposed by the FEI.