Authorities are trying to determine why someone fired at a white Chevrolet truck on the Boulder turnpike Friday morning, shattering the window.

The driver first told the Boulder County Sheriff’s Office about what happened at around 6 a.m. The 44-year-old Westminster man told deputies the window was blown out by a mystery vehicle between the Flatirons Crossing and McCaslin exits on US 36.

He says the car pulled up next to him and his driver’s side window shattered. Deputies later found a bullet hole.

Police say they don’t know what motivated the shooting. The suspect vehicle is described as an older white Toyota or Honda sedan.

Anyone who witnessed the incident is asked to call Boulder County Det. Jeff Pelletier at 303-441-3635. IF you wish to remain anonymous, you can contact Northern Colorado Crime Stoppers at 1-800-222-TIPS.