SANTA ROSA, Calif. (AP)—Lance Armstrong’s time-trial bike was stolen from the Team Astana truck during the night before Stage 1 of the Tour of California.

Armstrong rode the bike to a 10th-place finish Saturday in Sacramento during the Tour prologue. The race is his first competitive appearance in his native country since the seven-time Tour de France winner began his cycling comeback last month.

A few hours after the time trial, someone removed four bikes from the Astana truck outside the team hotel in Sacramento. Armstrong’s time-trial bike, which was closest to the door because he was delayed by a post-race trip to doping control, was taken along with race bikes belonging to Astana teammates Steve Morabito, Yaroslav Popovych and Janez Brajkovic.

Astana spokesman Philippe Maertens confirmed the theft to The Associated Press after it was reported by Armstrong himself on his Twitter feed. Armstrong later posted a picture of the bike, which has distinctive yellow-and-black wheels and the logo of his Livestrong foundation.

“There is only one like it in the world therefore hard to pawn it off. Reward being offered,” Armstrong wrote before jumping on his race bike for the 107-mile ride from Davis to Santa Rosa through a steady rainstorm.

Team Astana manager Johan Bruyneel also mentioned the thefts on his Twitter feed before he began following his riders. The racers all have backup bikes, and two-time defending Tour champion Levi Leipheimer’s bike wasn’t stolen.

Armstrong won’t need his time-trial bike again until Friday in Solvang, where the race holds its second time trial. That segment is crucial to Astana’s hopes of winning the overall team title.