(CNN) -- Italian climber Riccardo Ricco has become the third cyclist to be kicked out of this year's Tour de France after testing positive for the blood-booster EPO, but by far the most high profile.
Riccardo Ricco is the highest-profile of the three riders so far ejected from this year's Tour de France.
Ricco, who had already won two stages in the race and was lying in ninth position overall, was taken off the Saunier Duval team bus by police on Thursday and booed by spectators, Associated Press reported.
Saunier Duval subsequently pulled all of its riders, including eighth-placed Juan Jose Cobo and stage 10 winner Leonardo Piepoli, out of the race as they sought to investigate the situation.
"It's a team decision not to start the race," sporting director Matxin Fernandez told AP. "He's our leader, we can't act as if nothing happened. We suspend the activities of the team until we know what happened."
The 24-year-old Ricco, considered one of the world's top climbers, tested positive for EPO after the fourth stage, a time trial in the western town of Cholet.
He had come under suspicion about what he says is his naturally high hematocrit level -- the volume of red blood cells in his system. High hematocrit levels can suggest use of EPO, but do not confirm it.
"May the cheaters get caught. May they go away," said Tour president Christian Prudhomme.
"I said to the riders before the race, behind closed doors, that you have the key (to stop doping in cycling) ... Some didn't get the message."
Ahead of Thursday's 12th stage, Ricco was two minutes and 29 seconds behind overall leader Cadel Evans of Australia -- but was expected to close the gap when the race reaches the Alps next week.
He had won the sixth and ninth stages and was top of the King of the Mountains and Young Rider categories to confirm his status as one of the sport's rising stars.
Ricco came into the French event in fine form, having finished second overall at his home Giro d'Italia, winning two stages in the process.
He follows Spanish duo Moises Duenas Nevado and Manuel Beltran in being kicked out of the race following positive drug tests.
Duenas Nevado, of the Barloworld team, was also busted for using EPO on Wednesday, while veteran Liquigas rider Beltran was ejected last Friday after testing positive for the same substance.
The controversies have provided even more embarrassment for race organizers, already reeling after Floyd Landis was stripped of his 2006 title for steroid use and Michael Rasmussen was kicked off while leading last year's race for lying to his team to avoid a random drug test.
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