Authorities say NASCAR driver Tony Stewart struck and killed a driver who was walking on a dirt track during a race in upstate New York.
A video of the crash Saturday night at Canandaigua Motorsports Park showed driver Kevin Ward Jr. stepping toward Stewart's car before being hit and hurtled 50 feet.
The Ontario County Sheriff's Department would not identify the driver but said he was pronounced dead on arrival Saturday night at a hospital in Canandaigua.
Sheriff Philip Povero says the 42-year-old Stewart was "fully cooperative" as he was questioned and released. Povero says the investigation is not criminal.
Calls to Stewarts representatives were not immediately returned.
The three-time NASCAR champion is scheduled to race in NASCAR's event Sunday at Watkins Glen.