US police have found "no criminal behaviour" on race driver Tony Stewart's part but will continue their probe into the bizarre incident in which he struck and killed an up-and-coming driver.
Stewart, one of the most popular drivers in America's NASCAR stock car circuit, ploughed into 20-year-old Kevin Ward Jr. during a non-NASCAR race on a dirt track on Saturday night at Canandaigua Motorsports Park.
"At this time there are no facts that exist that support any criminal behaviour or conduct or that any probable cause of a criminal act in this investigation," Ontario County Sheriff spokesman Philip Povero told reporters on Monday.
Povero said they have interviewed Stewart and several others who witnessed the incident and they say Stewart, who was unhurt, has been cooperative.
Povero told reporters they are looking for more video footage of the crash as part of their ongoing investigation. He said they already have two videos of the incident.