Italy's reigning 50km walk champion Alex Schwazer has been withdrawn from the Olympics for failing a drugs test, a source with knowledge of the case confirmed to AFP on Monday.
The source said Schwazer, 27, tested positive for the banned blood booster EPO during a test conducted by the World Anti-Doping Agency (WADA) at a training camp in Oberstdorf, Germany.
The Italian Olympic Committee (CONI) said in a statement an athlete had been withdrawn from the Olympics for failing a drugs test but did not name the athlete or the sport.
Schwazer was a bronze medallist at the 2005 and 2007 World Championships before striking gold at Beijing four years ago.
He had been one of Italy's best medal hopes in London after a solid start to the season which saw him clock the fourth best time of his career.
WADA has warned the London Games would see the most rigorous testing regime in history, with more than 6,000 tests expected to be carried out during the fortnight-long sporting extravaganza.