NASCAR driver Tony Stewart hit and killed fellow driver Kevin Ward Jr. at the Empire Super Sprints series at Canandaigua Motorsports Park in upstate New York Saturday night.

Tony Stewart Hits, Kills Driver

Stewart hit Ward as he was walking on the track after crashing his car into the wall. While Ward was outside of his car, he had his arm raised and appeared to be yelling. One car managed to swerve around Ward. However, Stewart passed too close, making contact with him with the back of his car during his 14th lap, Ontario County Sheriff Philip C. Povero told CNN.

Police are investigating the matter and have said that Stewart has been cooperative. "Stewart has fully cooperated,” Povero said. "He acknowledges the collision with the driver."

Following the accident, Ward was taken by ambulance to a local hospital, but died of his injuries before he arrived.

Stewart’s spokesman Mike Arning released a statement on his behalf:

"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."

Stewart plans on racing at a NASCAR event at the Watkins Glen International race track on Sunday, reported CNN.