Authorities say 45-year-old Todd Allen Shields was charged with assault and other counts and placed on leave.
According to police, passenger Desirae Madrid recorded Shields fighting with a 21-year-old man after the man tried boarding the bus with a reduced fair ticket for minors. Police say the bus driver demanded identification, but the passenger refused.
Madrid told KSAZ-TV that's when she saw Shields pick the man up and throw him off the bus. Police say the video shows Shields attacking the man, who suffered minor injuries.
It was not known if Shields had an attorney.