A video of a San Antonio school police officer body-slamming a middle school girl to the ground is making the rounds online.

The short but controversial clip was uploaded online on April 5 and has led to an investigation of the officer, named Joshua Kehm, who works for the San Antonio Independent School district.

The 12-year-old girl is named Janissa Valdez and is a sixth grader at Rhodes Middle School.

In the video, Valdez can be seen struggling as the officer tries to keep hold of her and several other students watch. The officer then resolves to picking her up and slamming her against the floor to keep her still. Once face down on the ground Valdez doesn't move.

Valdez suffered a bruise on the face and couldn't remember being slammed. According to multiple reports, Valdez revealed that she never became violent towards the officer and was trying to keep two fellow students from fighting.

“You could actually hear her head hit the concrete. That’s what hurt me the most,” said the girl's mother, Gloria Valdez. “And he didn’t even seem like it bothered him. And he still handcuffed her after she was unconscious.”

Kehm has been placed on paid administrative leave while the incident is investigated.

Watch the disturbing moment below.