Story highlights Kaylee is nonverbal and has autism

"It almost feels like I failed her," father says

(CNN) A video showing a bus aide slapping a 6-year-old girl with autism has left an Illinois father heartbroken.

In the surveillance-camera footage, the unidentified aide strikes the little girl twice as she screams while riding to school in New Lenox, Illinois, a suburb of Chicago.

Nicholas Rushing said his daughter, Kaylee, is nonverbal. Rushing said he found out about the incident because the superintendent of the local school district contacted him and asked him to review the footage.

The video "broke my heart," he said.

The footage showed the woman had been touching Kaylee throughout the bus ride, denying her personal space, Rushing said.

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