The off-duty officer was driving eastbound in front of Broomfield High School on Monday, when a man in a silver Chevrolet truck pulled beside him.
Police say the driver of the truck, who was traveling in the opposite direction, leaned out the window, yelled something and pointed a black and clear colored weapon at the off-duty officer and fired twice.
Authorities say the off-duty officer was struck twice in the left temple, but was not injured.
The officer called 911 at about 12:10 p.m. and followed the vehicle until Broomfield Police arrived.
Police say they stopped the truck on Sheridan, just north of West 144 Avenue and arrested the driver, 18-year-old Cory Casady.
Authorities say they recovered a spring loaded pellet gun as well.
Casady was the state champion in the Class 4-A 140-pound weight class this year.
Casady was transported to the Broomfield County Jail and was booked on charges of felony menacing and reckless endangerment, police say.
Police aren't sure whether Casady knew the other driver was a police officer. The officer's name hasn't been released.
Authorities say they also interviewed three juvenile passengers from the vehicle and determined they were not involved in the incident.
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