A 16-year-old Michigan boy has been charged in the beating of a substitute school bus driver.

The Kalamazoo Gazette and WWMT-TV report the Kalamazoo teen has been charged as a juvenile with assault with intent to do great bodily harm less than murder.

Authorities say the teen was upset at how the 37-year-old driver was doing her job and threatened her Tuesday morning. She pulled over in Kalamazoo Township, about 45 miles south of Grand Rapids, where police say the teen attacked the driver, who suffered a broken finger, bruises and scrapes.

The Kalamazoo Public Schools district says the driver was following all rules and regulations at the time of the incident.

The boy is being held in a juvenile home and will appear in court April 3 for a pretrial hearing.