The 26-year-old Leopard-Trek rider crashed at high speed during the 20 kilometre descent from the Passo del Bocco on Stage Three from Reggio Emilia to Rapallo near Genoa, to the horror of watching spectators.

Weylandt lay motionless on the roadside and bleeding heavily from his nose and mouth as paramedics tried desperately to resuscitate him.

After 25 minutes, he was taken by helicopter to hospital where he was declared dead.

Race organisers cancelled the presentation for the stage winner, the Spaniard Angel Vicioso, and the new race leader, David Millar of Britain, as a mark of respect for Weylandt.

Giro d'Italia race doctor Professor Giovanni Tredici said: "Weylandt was the victim of a fall and we are still trying to reconstruct the dynamics of what happened.

"We tried immediately but he was already unconscious, his condition was already compromised.

"We tried for 40 minutes to resuscitate him but there was nothing we could do."

Weylandt had moved to the Leopard-Trek team earlier this year after turning professional with Quick Step in 2006.

He had won Stage Three of the same race last year, and also Stage 17 of the 2008 Vuelta a España.

He is the first rider to be killed in a crash in one of cycling's three main tours since Italian rider Fabio Casartelli in the 1995 Tour de France.

Leopard Trek's general manager Brian Nygaard said: "Today, our team-mate and friend Wouter Weylandt passed away after a crash on the third stage of the Giro d'Italia.

"The team is left in a state of shock and sadness and we send all our thoughts and deepest condolences to the family and friends of Wouter.

"This is a difficult day for cycling and for our team, and we should all seek support and strength in the people close to us."

Britain's Mark Cavendish, who finished safely in the peloton in the race, said on his Twitter page: "Things like this shouldn't happen.

"Absolutely sick to the stomach.

"My thoughts are with his family.

"RIP Wouter Weylandt."

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