Traffic cameras captured the image of a man in dark clothing and a baseball cap near the site where a woman died of a bullet wound to the head on Interstate 25, a discovery made while police investigated what they thought was a traffic accident.
Gwendolyn Bernard, 53, died early Sunday morning.
"We can't rule anything out at this point," Detective Don Litton of the Pueblo Police Department said Tuesday.
Police did not know if the man captured on camera by a Colorado Department of Transportation camera near Interstate 25 and the U.S. 50 bypass had anything to do with Bernard's death. Litton said they were trying to identify the man.
Detectives have said they don't suspect homicide in the death and believe Bernard, a massage therapist and single mother, was alone in her pickup truck.
County Coroner James Kramer said she died of a gunshot wound to the right side of her head.
Investigators recovered a .22-caliber revolver from the vehicle.
Kramer said his office was conducting microscopic analysis to determine at what distance Bernard was shot.