WETTINGEN, Switzerland -- Alessandro Petacchi won the fourth stage of the Tour of Switzerland on Tuesday, after a multi-bike crash took down many riders in a frenzied final sprint.
Tony Martin of Germany retained the overall race lead despite being delayed by the spill at the end of the 119-mile ride from Schwarzenburg to Wettingen.
Organizers blamed the crash on British rider Mark Cavendish. The race jury gave Cavendish a 30-second penalty for a "dangerous" move out of his line during the final sprint.
"About 1,000 meters from the finish, I could tell it was going to be a nervous sprint, caused partly by the wind and a narrow path between the barriers," said Martin of team HTC-Columbia.
Lance Armstrong, who is using the nine-day event as a final warmup before the Tour de France next month, was not mixed up in the crash, his RadioShack team said.
"What a day. What a final," Armstrong wrote on his Twitter feed. "Nasty crash in the sprint that involved many. Damn, this game is dangerous. Hope all the guys are ok."
The sprint specialist Cavendish and Heinrich Haussler of Germany bumped and tumbled to the road with 30 yards left, causing several others to go down.
Haussler, a Cervelo team rider who won Sunday's second stage, and Arnaud Coyot of France were taken to hospital for treatment, race organizers said.
Details on their injuries weren't immediately available.
Cavendish's HTC-Columbia team said he sustained bruises and scrapes but was otherwise unhurt. He'll have precautionary X-rays before a likely start in the fifth stage Wednesday.
Under race rules, riders in the main bunch at the front all receive the same final times when a crash occurs during a sprint within the last mile.
Therefore, Petacchi clocked the same time as 104 other riders, including Martin, Armstrong and Cavendish: 4 hours, 57 minutes, 33 seconds.
Overall, Martin leads Fabian Cancellara of Switzerland by one second, while Thomas Lovkvist of Sweden is third, nine seconds behind. Armstrong is 22nd, 30 seconds behind the leader.
Armstrong, seen chatting with riders including Cavendish, didn't speak to reporters after the stage.
Cavendish, a 25-year-old native of the Isle of Man, is one of the world's top sprinters. He won six stages at the Tour de France last year.
Team HTC-Columbia said its leader Michael Rogers of Australia -- the winner of the Tour of California last month -- pulled out of the race before the stage on Tuesday. He plans to focus his training in high altitude ahead of the Tour de France.
The stage Wednesday takes riders on a 107-mile course from Wettingen to Frutigen. The race ends Sunday with a time trial in and around Liestal.