UPDATE: Tony Stewart has released a statement following the death of Kevin Ward Jr:
"There aren't words to describe the sadness I feel about the accident that took the life of Kevin Ward Jr. It's a very emotional time for all involved, and it is the reason I've decided not to participate in today's race at Watkins Glen. My thoughts and prayers are with his family, friends and everyone affected by this tragedy."
UPDATE: Tony Stewart’s racing team manager Greg Zipadelli said Stewart will not race in NASCAR’s event Sunday at Watkins Glen. Regan Smith will take Stewart's place. Earlier, Zipadelli had called Sunday's race ‘‘business as usual."
NASCAR also released a statement on the incident: "Our thoughts and prayers go out to the family, friends, and fellow competitors of Kevin Ward Jr. We support Tony Stewart's decision to miss today's race and we will continue to respect the process and timeline of the local authorities and will continue to monitor this situation moving forward."
More: Who was Kevin Ward, Jr?
EARLIER: CANANDAIGUA, N.Y. -- NASCAR driver Tony Stewart struck and killed a driver who had climbed from his car and was on the track trying to confront Stewart during a sprint car race Saturday night in upstate New York, police said.
Ontario County Sheriff Philip Povero said his department’s investigation is not criminal and that Stewart was ‘‘fully cooperative’’ and appeared ‘‘very upset’’ over what had happened. Speaking at approximately 3 a.m. ET on Sunday, Povero confirmed a driver -- later identified as Kevin Ward Jr., 20, from Port Leyden, N.Y. -- was taken to a local hospital, where he was pronounced dead on arrival. Povero said the investigation was ongoing and no charges were pending at this time.
"[Stewart] was visibly shaken by this accident,’’ Povero said.
A video of the crash at Canandaigua Motorsports Park showed driver Ward Jr., wearing a black helmet and firesuit on a dimly lit track, walking toward Stewart’s car before being hit and hurtled 50 feet.
A man who said he was at the track during the accident spoke to Bob Pockrass of Sporting News.
Tyler Graves, a sprint-car racer and friend of Ward's, told Sporting News in a phone interview that he was sitting in the Turn 1 grandstands and saw everything that happened.
"Tony pinched him into the frontstretch wall, a racing thing," Graves said. "The right rear tire went down, he spun on the exit of (Turn) 2. They threw the caution and everything was toned down. Kevin got out of his car. … He was throwing his arms up all over the place at Tony for most of the corner.
"I know Tony could see him. I know how you can see out of these cars. When Tony got close to him, he hit the throttle. When you hit a throttle on a sprint car, the car sets sideways. It set sideways, the right rear tire hit Kevin, Kevin was sucked underneath and was stuck under it for a second or two and then it threw him about 50 yards."
On its Facebook page, the track wrote, "Canandaigua Motorsports Park will not have an official statement on that accident that happened in the [Empire Super Sprints] race until tomorrow. Please pray for the entire racing community of fans, drivers, and families."
Povero said the 25-lap race was under caution when Ward was struck. Stewart’s car was behind another before he hit Ward.
‘‘The first car swerved to avoid the driver,’’ Povero said.
Povero said the driver was pronounced dead Saturday night at a Canandaigua hospital. Stewart was unhurt.
A witness said it appeared Ward was trying to confront Stewart, the three-time NASCAR Sprint Cup Champion. The video showed Ward standing to the right of Stewart’s familiar No. 14 car, which seemed to kick out from the rear and hit him.
‘‘The next thing I could see, I didn’t see (the other driver) anymore,’’ witness Michael Messerly said. ‘‘It just seemed like he was suddenly gone.’’
Povero said the 43-year-old Stewart, a frequent competitor at local sprint car events, was questioned and released. The sheriff asked for people who recorded video of the crash to provide copies for investigators to review.
A spokesman for Stewart’s racing team called Ward’s death a ‘‘tragic accident.’’
‘‘Our thoughts and prayers go out to his family and friends,’’ the spokesman said in a statement. ‘‘We’re still attempting to sort through all the details.’’
The dirt track, about 30 miles southeast of Rochester, canceled the remainder of the race and later posted a message on its Facebook page encouraging fans to ‘‘pray for the entire racing community of fans, drivers, and families.’’
It said a statement on the crash would come later Sunday.
Ward’s website said he began racing go-karts in 1998 at age 4, but didn’t start driving sprint cars until 2010. The 20-year-old was Empire Super Sprint rookie of the year in 2012 and this year was his fifth season racing the Empire Super Sprints.
Stewart was involved in a July 2013 accident at Canandaigua that seriously injured a 19-year-old driver. He later took responsibility for his car making contact with another and triggering the 15-car accident that left Alysha Ruggles with a compression fracture in her back.
After Saturday’s accident, ambulances, fire trucks and police arrived within moments, Messerly said. Fans filed out in stunned silence, he said.
The accident Saturday came almost exactly a year after Stewart suffered a compound fracture to his right leg in a sprint car race in Iowa. The injury cost him the second half of the NASCAR season. Stewart only returned to sprint track racing last month. He didn’t return to racing in any form until February when preparation for NASCAR’s season-opening Daytona 500 began.
Stewart was a spectator at the Knoxville Nationals in Iowa on Tuesday, the one-year anniversary of the accident, and posted on his Twitter account: ‘‘Thank you to everyone that worked so hard to get me back to where I'm at today. It’s your life, live it!’’
Roughly three hours after Saturday night’s accident in New York, Donny Schatz, a sprint car driver for Tony Stewart Racing, won the prestigious Knoxville Nationals in Iowa for an eighth time.
‘‘I was just told there was an incident involving Tony. I don’t know to what extent or what’s happening,’’ Schatz said.
Stewart is co-owner of Stewart-Haas Racing, the four-team NASCAR organization that fields cars for Stewart, Kevin Harvick, Kurt Busch and Danica Patrick. He’s struggled a bit this year since returning from his leg injury, and heads into Sunday’s race winless on the season and ranked 19th in the standings.
Stewart was scheduled to start 13th on Sunday at Watkins Glen International in south central New York state. He has just five races remaining to either score a win or move inside the top 16 in points to grab a valuable spot in NASCAR’s championship race.
-- The Associated Press contributed to this report