UPDATE (AP): Tony Stewart will not race Sunday following the death of a sprint car driver who was struck and killed by Stewart at an upstate New York dirt track.
Greg Zipadelli, competition director for Stewart-Haas Racing, said the three-time NASCAR champion "feels strongly" he should not race at Watkins Glen following Kevin Ward Jr.'s fatal accident.
Regan Smith will replace Stewart in the car.
Race car driver Kevin Ward, Jr. was walking on the dirt track of Canandaigua Motorsports Park in upstate New York when he was struck by the sprint car driven by NASCAR driver Tony Stewart.
Stewart is reported to be fully cooperating with police following the deadly accident during Saturday night's Lucas Oil Empire Super Sprint.
Ward's body lay motionless after the incident as race track safety crews rushed to his side. The 20-year-old was rushed to a nearby medical center, but died from injuries suffered in the crash.
Spectator video shows how the tragic accident unfolded. It followed an encounter between Stewart and Ward on a lap just before the deadly crash.
On the second turn of lap 13 of the 25 lap race, the right rear tire of Stewart's car (14) strikes the left front tire of Ward's car (13).
Ward's car hits the wall and spins 2 1/2 times before coming to rest. Once the car has settled, the video shows the driver unbuckling his safety harness, climbing out of the car and walking into the middle of the dirt track, pointing his finger and waving as other cars raced by — within a few feet.
As Stewart's car approached turn 2, Ward steps closer at the same moment Stewart's car appears to slide into him on the dirt track.
Ward's body is dragged and then appears to be thrown into the air, before coming to rest more than 50 feet from the point of initial contact.
Following the accident, the race track was shut down for the night and Stewart's car was impounded as the Ontario County Sheriff's Office began an investigation.
The video of the incident can be seen here. (Graphic content and strong language warning)
CNN spoke with Philip C. Povero of the sheriff's office about the incident. Povero told the cable news outlet, "Stewart has fully cooperated with investigation. He acknowledges the collision with the driver."
USA Today reports that local authorities have an ongoing investigation, but the race track crash is currently not considered to be a criminal matter.
Tony Stewart's company, Stewart-Haas Racing, released a statement through spokesman, Mike Arning:
"A tragic accident took place last night during a sprint car race in which Tony Stewart was participating. Tony was unhurt, but a fellow competitor lost his life. Our thoughts and prayers go out to his family and friends. We're still attempting to sort through all the details and we appreciate your understanding during this difficult time."
Stewart was scheduled to start Sunday's Cheez-It 355 Watkins Glen International NASCAR race.
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