A monster truck crashes into a large portion of the crowd at an airshow in Mexico, killing many.

A MONSTER truck has crashed into a grandstand in Mexico and debris have showered an IndyCar crowd in Houston in a deadly weekend for motorsport fans.

Up to 13 spectators, two drivers and one official were injured in the final lap of the IndyCar race in Houston overnight.

Most were treated at the scene but two people were taken to a local hospital.

Early reports suggest driver Dario Franchitti has suffered a spinal fracture, concussion and a broken right ankle in the serious crash at turn 13 on the Houston track. The three-time Indy 500 winner is expected to remain in hospital under observation for several days.

Australian driver Will Power went on to win the event.

Earlier last night Australian time, a monster tuck crashed into a grandstand after its brakes failed during a stunt show in northern Mexico. Eight people were killed and up to 60 others injured.

Carlos Gonzalez, spokesman for the Chihuahua state prosecutors' office, said the driver appeared to have lost control of the truck after leaping over cars it was crushing during a demonstration at the "Extreme Aeroshow" on Saturday.

Video taken by a spectator shows the truck making an initial pass over two cars, then making a second pass at higher speed, coming down sharply nose-first and bouncing violently before piling straight into the crowd, which stood directly in the path of the monster truck, unprotected by any wall or barrier.

Some witnesses said the driver appeared to have hit his head on the interior of the truck as he drove over the old cars, with at least two reporting seeing his helmet come off before the massive vehicle drove into the crowd of terrified spectators, who tried to flee.

"I fell over, and when I turned around I saw the tyre very close. It hit me and threw me to the other side," Jesus Manuel Ibarra, 41, said as he was treated for injuries to his arm and hip.

Mr Gonzalez said the accident killed at least one child and hurt 80 people, 46 of whom remained in hospital early Sunday. He said the number of dead and injured could rise as officials received updated information. The local health system listed the names of 67 injured people on its Facebook page, calling urgently for blood donations and help from local doctors and nurses.

Mr Gonzalez said prosecutors were looking into the possibility of a mechanical failure that left the driver unable to release the gas pedal. Several witnesses said, however, that the driver appeared to have become incapacitated when he struck his head during the show, in which the truck drives at high speed over smaller cars, leaping into the air as it crushes their roofs.

Spectator Daniel Dominguez, 18, said he was happily watching the show with a group of relatives when the truck came down hard in the middle of the cars.

"The driver hit his head and his helmet flew off," Mr Dominguez said. "The truck came directly at where we were."

His 11-year-old sister was in surgery for injuries to her legs, and his mother was treated for minor contusions.

The air show was cancelled after the accident that happened during the second day of the three-day show in a park on the outskirts of Chihuahua, the capital of Chihuahua state.