(CNN) A Pennsylvania daycare worker has lost her job after she allegedly pushed a 4-year-old girl down a flight of stairs.

"I think it's every parent's worst nightmare that sends their kid to daycare," Upper Darby Police Superintendent Michael Chitwood told reporters.

In the video, a daycare worker can be seen shoving the child in the back at the top of the stairs. The little girl falls out of the frame and the woman glances up at the camera.

Police identified the woman as 52-year old Sarah Gable. She has been fired from the Child Care of the Future daycare center and charged with simple assault and endangering the welfare of a child.

She was released from jail on $25,000 bond.

CNN has tried to reach Gable for comment but has not been successful.

Shawayne Tavares is a caretaker at the daycare center in Clifton Heights, a suburb of Philadelphia. She saw the incident occur last Friday while watching the cameras that had just been installed at the center.

"It still hurts me, just seeing the video," Tavares told CNN affiliate KYW. "The little girl was really shaken up. Her eyes were literally like, 'help me.'"

Tavares said she immediately confronted Gable after the incident and told her, "What are you doing? We don't do this to children."

The 4-year old girl suffered a knee injury but went back to daycare the next morning.

But Tavares said "she was a little scared of the steps."

CNN also attempted unsuccessfully to reach Child Care of the Future daycare center and the Upper Darby police department for comment.