07/19/2012 02:49 EDT | Updated 09/18/2012 05:12 EDT

World champion Mark Cavendish crashes on Tour de France because of spectator's flag

BAGNERES-DE-LUCHON, France - World champion Mark Cavendish says a spectator waving a flag caused him to crash about three kilometres from the finish of the 17th stage of the Tour de France.

Cavendish, who finished 31 minutes, 32 seconds behind stage winner Alejandro Valverde of Spain, said on Twitter that the flag wrapped round his handlebars.

Cavendish, whose main goal this season is the Olympic road race next week, said his legs were "swollen" but he expects to start Friday's stage.

Cavendish added his bike was broken in the crash.