MEAUX, France -- Four-time champion Lance Armstrong was thrown from his bike but not seriously hurt in a crash involving about 35 riders sprinting for the finish line in the first full stage of the Tour de France on Sunday.

Alessandro Petacchi of Italy, just ahead of the pack that crashed, won the stage and immediately blamed Tour organizers for the pileup, saying the corner where the accident took place, a few hundred yards from the finish, was dangerous.

"We're made to wear a helmet, but then they give us a dangerous corner so close to the finish. That's something that should not be on the route in such an important race as the Tour de France,'' he said.

A Spanish rider, Jose Enrique Gutierrez, was first to go down, slipping in the turn. Other riders, including Armstrong, who is vying for a record-tying fifth consecutive title, piled into him.

Many other cyclists were blocked behind the mass of fallen riders and bikes.

Tour doctors said five riders were taken to a hospital for X-rays, including U.S. rider Tyler Hamilton, a former teammate of Armstrong's now cycling for the Danish CSC team. Hamilton has a broken collarbone and appears to be doubtful for the rest of the Tour.

"It doesn't look good,'' said team spokesman Brian Nygaard. He said a team doctor would examine Hamilton before deciding whether he could keep racing.

A French rider, Jimmy Casper, injured his neck.

Armstrong completed the race on the bike of U.S. Postal teammate Jose Luis Rubiera. Armstrong had a flat, and the wheel wouldn't turn, so Rubiera got off his bike and handed it to Armstrong.

"It is never good to crash, but it wasn't that bad,'' Armstrong said. "We all just fell over and got piled on top of.

"It kind of makes for a hard day but it's good to get the first one (stage) over with. Unfortunately, we had a bad ending at the end of it, but it's OK.''

The 31-year-old Texan bruised his right thigh and scratched his left shoulder, U.S. Postal team spokesman Jogi Muller said. Armstrong held his hand to his back as he later boarded the team bus, but he had no visible injuries.

Two of Armstrong's teammates also went down. George Hincapie sustained cuts on his left knee, and Vjatceslav Ekimov had scratches, Muller said.

Tour competition director Jean-Francois Pescheux denied the course was at fault.

"If people tell me today that it was dangerous, then they should stop cycling,'' he said.

Before the race, Armstrong said his goal for the day was to stay out of trouble and save his strength for a team time trial later in the week and punishing mountain stages, where he often leaves rivals in his wake.

"It's a dangerous week, as we all know, and you need to avoid problems and accidents,'' he said.

Petacchi beat Robbie McEwen of Australia in the dash for the finish. German Erik Zabel was third. Petacchi covered the 104-mile course in 3 hours, 44 minutes and 33 seconds. McEwen and Zabel were just behind.

Australian Bradley McGee retained the yellow jersey as the overall leader. McGee won the opening individual 4.03-mile time trial in Paris on Saturday.

Armstrong is eighth in the overall standings, with 19 days of racing remaining.

The race started from Le Reveil Matin, a restaurant in the southeastern Paris suburb of Montgeron. The first Tour started there in 1903.

The riders first cycled south before turning east and then north to finish in Meaux for the first time. Meaux, a town of 50,000 known for its Brie cheese and mustard, is about 25 miles east of Paris.

The 104-mile route took the riders past ripened fields of golden wheat, the lush green forest of Fontainebleau and through picturesque villages. Waving fans along the route cheered the riders.

Before the race, the riders first gathered at the Stade de France, the stadium in northern Paris that hosted the 1998 soccer World Cup final, and paraded from there through Paris to the start at Montgeron.

On Monday, the Tour's third day, the riders cover 126.8 miles, skirting Champagne country and the cathedral town of Reims, where French kings were crowned. They finish in Sedan, a town on the border with Belgium where German troops broke through during their invasion of France in 1940.