Orthez, July 25:

Dozens of Tour de France riders demonstrated their anger over repeated doping scandals by staging a silent protest at the start of Wednesday’s 16th stage. The protest came a day after star rider Alexandre Vinokourov and his Astana team were sent home after he tested positive for a banned blood transfusion.

On Wednesday, the pack of riders split into two groups: those who took the start as normal — including controversial race leader Michael Rasmussen — and those who protested by hanging back for a few minutes. The riders let Rasmussen, star sprinter Tom Boonen and others not involved ride away — but caught up with them further down the road.

Fans booed Rasmussen, who later won the stage, at the start. The Dane is under a cloud of suspicion because he skipped doping tests before the Tour began. The protest contributed to a 13-minute delay to the scheduled start time of the race. The race ends on Sunday.

Many of the riders involved in the symbolic protest were from French teams that have long complained that doping is ruining the sport. The German squad Gerolsteiner also took part in the protest. Some of the French teams involved included Credit Agricole, Cofidis, FDJeux and Bouygues Telecom.