A stunning video shows a day care worker pushing a four-year-old girl down a flight of steps.

Authorities in Upper Darby, Pa., have charged 52-year-old Sarah Gable with simple assault and child endangerment after surveillance video footage showed her pushing the girl.

Police said Gable was fired after the owners of Child Care of the Future saw what happened. Officials said the video camera was installed a half-hour before the incident.

In the video, Gable pushes the girl down four flights of steps before seeming to realize the presence of the camera. She then helps the girl down the next flight of stairs.

The child sustained a knee injury, according to police.

Watch the shocking video from Inside Edition above.

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