UPDATE (11:05am 8/10): Tony Stewart will NOT race on Sunday in the NASCAR race at Watkins Glen.  Greg Zipadelli made the announcement Sunday morning.  Regan Smith will take his place.  Click here to read more.

Original Story:

The Ontario County Sheriff's Department announced early Sunday that Tony Stewart struck and killed a fellow driver with his sprint car Saturday night during a dirt-track race at Canandaigua Motorsports Park in New York.

According to multiple reports, the driver that was killed is Kevin Ward, Jr.

Stewart's car allegedly struck Ward after he got out of his car to confront Stewart about earlier contact between the two on during the race. Video of the incident was posted on Youtube late Saturday night, and it is extremely graphic.

Click Here To Watch The Video at Deadspin.com.

According to Foxsports.com, Stewart-Haas Racing released this statement Sunday morning: "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."

Sheriff Povero said the investigation it is not a criminal investigation.

Numerous reports also state that NASCAR is investigating, and Stewart is expected to race in the NASCAR Sprint Cup Series race at Watkins Glen International on Sunday.

Here is video of the press conference with Ontario County Sheriff Povero.

Photo: Getty Images