Sgt. Trent Crump says the employee found the video Tuesday but the incident was videotaped Jan. 25. He says it was filmed while Larrison was responding to a call from the girl's school and her mother saying she was drunk and had pushed a male teacher.
Crump says that "at face value, the video is concerning to us."
Larrison's phone number is unlisted, and it's unclear whether he has a lawyer.
Crump says Larrison has no previous complaints of excessive force.