HOUSTON -- Scott Dixon took control of the IndyCar championship race when Helio Castroneves suffered his second mechanical failure in two days at the Grand Prix of Houston, where the race ended when Dario Franchitti's car went airborne into the fence on the final lap.
The Houston Fire Department told KTRK-TV in Houston that at least 13 fans were injured in the crash. Most are being treated at the scene, but at least two people were transported to the hospital, according to KTRK-TV.
The accident in Turn 5 happened when Franchitti, the four-time IndyCar champion, made contact with Takuma Sato. Franchitti's car launched over Sato's and sailed into the fence, showering debris into the grandstand before Franchitti's car came back onto the track.
E.J. Viso then hit Sato's car.
The caution came out to freeze the field, allowing Penske Racing's Will Power to win the race and halting Dixon's final attempt for a doubleheader sweep.
Dixon settled for second. After coming into the Houston doubleheader trailing Castroneves by 49 points, Dixon goes into the Oct. 19 season finale with a 25-point lead.
There was no celebration, though, for Dixon or Power, who raced to his second victory of the season. Both had to drive through the wreckage from the three-car accident and past Franchitti, who sat inside his car waiting for medical attention.
Dixon waved to his teammate and got only a slight head nod back, and team owner Chip Ganassi rode a scooter out to the scene. Franchitti was placed on a stretcher and taken by ambulance to a hospital complaining of a sore ankle and back.
"Dario definitely got into the fence pretty hard," Dixon said. "All in all I hope that he's OK and obviously the fans. The fence took a pretty good hit there."
It appeared parts and pieces from Franchitti's car flew into the grandstand. IndyCar said one series official was taken to a hospital to be treated for minor injuries. There was no immediate word on potential injuries to fans.
Castroneves, who also had a gearbox problem in Saturday's race, finished 23rd. He had started on the pole, got a great jump on the standing start to get past Dixon for the lead, but Dixon was screaming on his radio within minutes that Castroneves' car was leaking oil everywhere and it was splashing onto Dixon's tires and visor.
Castroneves said little to his Penske Racing team, but detected a vibration in his car with every shift of the gears after just a handful of laps. The problem worsened and he came to a complete stop on the course at Reliant Park after just 11 laps.
"It's frustrating and disappointing," Castroneves said. "It hurts. It really hurts."
His car was towed to the garage with a broken gearbox, Castroneves made the long walk back still wearing his helmet, and team owner Roger Penske retreated without comment into a team transporter.
The team eventually replaced the gearbox and Castroneves returned to the track, 36 laps down and needing a miracle in Fontana, where the three-time Indianapolis 500 winner was fastest during an open test last week.
Information from The Associated Press was used in this report.