AIGLE, Switzerland — Polish brothers Pawel and Kacper Szczepaniak have been suspended after failing doping tests when finishing 1-2 in the under-23 Cyclo-cross World Championship race.

The International Cycling Union said Thursday they tested positive for the banned hormone EPO in urine samples taken after the race Jan. 30 in Tabor, Czech Republic. EPO boosts endurance by increasing the production of oxygen-carrying red blood cells.

The UCI said the Szczepaniaks had been under suspicion before the gold-medal race.

"The blood samples collected before the event from (Pawel and Kacper) Szczepaniak had already shown, within the biological passport program, that the blood profiles of these two riders were suspect," the UCI said in a statement.

The Szczepaniak brothers have been provisionally suspended until the Polish cycling federation conducts disciplinary hearings. They can ask to be present for testing of their back up samples at a World Anti-Doping Agency-accredited laboratory.

French rider Arnaud Jouffroy finished third in the under-23 worlds race, and could receive the gold medal if the Szczepaniaks are found to have committed a doping violation and disqualified.