Marcus Burghardt of Germany won the 18th stage of the Tour de France Thursday, leading a two-rider breakaway as the race left the Alps.

Carlos Sastre of Spain retained the yellow jersey.

Burghardt, a 25-year-old Team Columbia rider, and Carlos Barredo of Spain finished far ahead of the main pack at the end of the 196.5-kilometer ride from Bourg-d'Oisans to Saint-Etienne. France's Romain Feillu came in third at the front of the chasing group

The German raised his fists in the air and clapped as he crossed the finish, while Barredo banged his handlebars in frustration. They finished in 4 hours, 30 minutes, 21 seconds for the ride through minor mountains.

Sastre and his main rivals in the title finished 6:53 behind.

Barredo came into the stage more than 2 hours behind Sastre, and Burghardt was more than three hours back. The two riders consistently attacked each other in the last 10 km, and at times chatted.

Sastre leads CSC teammate Frank Schleck of Luxembourg by 1:24, and Bernhard Kohl of Austria is third, 1:33 behind. Cadel Evans of Australia is fourth, 1:34 back.

Today's stage takes riders through the plains along 165.5 km from Roanne to Montlucon. The final shakeout is expected in tomorrow's time trial from Cerilly to Saint-Amand-Montrond.

Italian rider Damiano Cunego crashed during the stage, resuming racing a long way behind the main pack after getting treatment from the race doctor.

Television images showed the Lampre team rider having a bandage attached by a medic to his chin. His jersey was ripped and torn.

Earlier, French customs stopped and searched a car driven by Johnny Schleck, father of riders Frank and Andy, during the 18th stage.

"We were looking for doping substances but the check was negative so we let him (Johnny Schleck) go," a customs spokesman said.

"Why would I have banned substances?" Johnny Schleck told RTL radio. "My sons are clean. With all these tests they have been undergoing, how would they not be clean?"

Frank Schleck declined to comment when asked for a reaction at the end of the stage.

Customs officers had stopped the car driven by Johnny Schleck, who drives guests around for one of the Tour sponsors, 35 kilometers into the stage at Grenoble. He was asked to step out of the car at a roundabout and was searched by a police officer.

He was then asked to drive the car towards the other side of the roundabout, where the car was searched by customs officers for 30 minutes.

"Two vehicles were searched: one in which nothing was found; and from the other - the one of Frank Schleck's father - some products were taken for verification," said Raphael Grandfils, a state prosecutor. "It turns out that this was not about forbidden products, but normal medicines."

Source: Shanghai Daily/Agencies