Bradley Wiggins, Tom Boonen pull out

CHATEAUROUX, France -- British rider Bradley Wiggins and former world champion Tom Boonen of Belgium have pulled out of the Tour de France.

Wiggins was caught in a big crash that took down several riders late in the seventh stage between Le Mans and Chateauroux on Friday. Boonen failed to recover from injuries he suffered in a crash this week.

Wiggins was one of about 20 riders caught near the back of the peloton with 23 miles to go in the 135-mile flat stage.

Wiggins, who was holding his left arm, grimaced in pain after the crash. Organizers announced Wiggins had pulled out several minutes later, and the team said Wiggins had a broken collarbone.

Boonen quit 55 miles into the seventh stage. He won the best sprinter's green jersey in 2007.

Boonen crashed Wednesday and finished more than 13 minutes behind the main pack.

The 31-year-old Wiggins had made a bright start to the race, helping his Sky team finish third in Sunday's team time trial. He was in sixth place overall.

Wiggins finished fourth in the 2009 Tour, his best finish, and had won the pre-Tour Dauphine Libere stage race to boost his confidence heading into the Tour.

Veteran American rider Christopher Horner also was caught as several riders went down in the crash, but the 39-year-old RadioShack rider was able to ride on.

Sprint ace Tyler Farrar, winner of Monday's third stage, also went down. But the Garmin-Cervelo rider seemed unharmed, gettting back on the bike moments later.

The first week of the Tour has had several crashes, with three-time defending champion Alberto Contador of Spain fortunate to escape with minor cuts and bruises after crashing on Wednesday's fifth stage.

Information from The Associated Press was used in this report.