A cell phone video of the incident shows a man who serves in an undefined safety role at the school pushing the student down the stairs. The girl is seen lying on the floor when she is approached by a woman who appears to be a teacher or administrator at the South Side school. The girl then gets up and moves toward the guard, who appears to punch the girl in the face.
"Immediate action was taken to remove this individual from his position while the investigation continues," CPS said in a statement about the incident.
CPS officials say they have contacted the Chicago Police Department.
The 16-year-old student's mother, who declined to give her name to NBCChicago, said the incident happened Tuesday, May 21 and her daughter went to the emergency room with injuries sustained in the encounter.
Students who declined to be interviewed on camera said they believed the safety official was trying to intervene in a fight between two students, one of whom is the girl in the video. Witnesses said the girl began hitting the guard about the head and chest as he tried to separate her from an altercation.
CPS does not condone the behavior.
"The safety of our students is our top priority," CPS spokeswoman Becky Carroll said. "CPS takes matters of employee misconduct very seriously, especially when it involves an employee whose job it is to ensure the safety of students."
(Photo: NBC Chicago screen shot.)