WATKINS GLEN, N.Y. (AP) -- Tony Stewart says "there aren't words" to describe his sadness over the collision that killed Kevin Ward Jr.
In a statement released by spokesman Mike Arning, Stewart says "my thoughts and prayers are with his family, friends and everyone affected by this tragedy."
The three-time NASCAR champion struck and killed Kevin Ward Jr. with his car on Saturday night as Ward walked toward it following contact between the two during their race at Canandaigua Motorsports Park.
The full text of the statement read: "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."
Stewart's team had said earlier Sunday that Stewart would be behind the wheel of his No. 14 Chevrolet when the green flag waved. Regan Smith drove Stewart's car instead.
Mobile users watch video here: http://bit.ly/1oBDIgz