Shocking video shows the moment a semi-truck slammed into a police car in Wisconsin.
The truck failed to stop at a red light before hitting the driver side of the vehicle.
The officer, who was uninjured, was initially trapped in the car.
The driver of the semi was cited for Operating Too Fast for Conditions.
Authorities used the incident as an example to remind motorists to "drive within safe speeds" so they can stop in time to avoid crashes
