COMMACK - A bus aide accused of assaulting an autistic boy was arraigned today.

Desiree Johnston says her 5-year-old son Connor, who has autism, was assaulted by a bus aide on the way home from a Commack elementary school. She says his arm is broken.

Police say 39-year-old Richard Mason, of Brentwood, was trying to discipline the boy. They say he grabbed the child's arm and twisted it behind the student's back.

Mason told News 12 Long Island, "He was pounding his hand against the window and to prevent the window from shattering, I blocked him." Mason says he didn't hurt the boy.