The "Fast and the Furious" star and his friend, Roger Rodas, were killed Saturday afternoon when the car Rodas was driving smashed into a light pole.
"Santa Clarita Valley Sheriff's Station traffic investigators are continuing to document the investigation and have received eyewitness statements that the car involved was traveling alone at a high rate of speed," Variety quoted a Los Angeles County Sheriff's Department spokesman as saying Monday. "No eyewitness has contacted the Los Angeles County Sheriff's Department to say there was a second vehicle. The posted speed limit in the area of the collision is 45 mph."
The statement contradicts some media reports saying police are following up on a phone tip that Rodas was racing another car at the time of the crash.
Autopsies on the bodies of Walker and Rodas are scheduled for Tuesday, Variety said.