The San Antonio Express-News reports that the officer, identified as Joshua Kehm, stepped in after two girls "became verbally aggressive" the afternoon of March 29, according to a San Antonio Independent School District spokeswoman. Kehm has been placed on paid administrative leave as police and administrators investigate the incident. 

The girl in the video, 12-year-old Janissa Valdez, told WOAI-TV that she wanted to have a conversation with the other girl.

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"You could just hear where she hits the ground. And it's nothing but concrete, cement," Janissa's mother, Gloria Valdez, told WOAI. "She wasn't moving. She was just knocked out. I wanted answers, and nobody could give me answers."

"Because I wasn't going to do anything," she told WOAI.

Kehm declined to make a statement, according to WOAI.

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