Two Houston, Texas school district police officers pinned a 15-year-old girl face down on the floor on Tuesday because she didn’t want to relinquish her cell phone to an assistant principal.

The girl, sophomore Ixel Perez, weighs 70 pounds, according to her brother. She attends Sam Houston High School.

In a video of the incident, one of the cops who tackled the girl can be seen ramming his knee into the side of her head, reports local CBS affiliate KHOU.

The incident happened after the teacher in Perez’s reading class busted her using a cell phone in class.

Student cell phone use is prohibited at Sam Houston High. Students caught using cell phones are required to give their phones to school officials. They must then pay a fine at the end of the day to get their phones back.

The reading teacher ordered her to leave the classroom and go into the hallway.

Once Perez was standing in the hallway, an assistant principal approached her and demanded that she give up her phone. Perez said she wanted to keep her phone because her mother was having medical problems.

When Perez tried to walk away, the assistant principal called the police. Because of a cell phone.

Three cops from the Houston Independent School District’s police force showed up shortly thereafter. Two campus cops participated in the takedown. A third stood around and watched his colleagues.

“Both of the cops just tackled her down to the floor,” said another student, Gustavo Lucio, to a KHOU reporter. Ironically, Gustavo filmed the incident with his own cell phone.

“They put her knee on her head and after that they just arrested her, took her phone,” Gustavo explained. “The cop just said you can’t use your phone and after that, no words no nothing, just actions, grabbed her, threw her down.”

Perez, who was still an emotional wreck, discussed the incident on Wednesday morning as she stood outside the school with her mother and brother by her side.

“It was embarrassing,” she said.

“I just didn’t want to give up my phone,” she added. “She asked me for the phone and I didn’t want to give it to her, because I was scared. I ended up walking down the stairs trying to get away.”

Perez also noted that she was speaking with her mother when the police officers accosted her.

“One grabbed my hand. I didn’t want to let go of my phone because I was on the phone with mom,” she told KHOU.

“We all know it was wrong,” Perez’s brother, Chris Cardenas, told the station. “It doesn’t take three cops to take down one teenage girl.”

The school district issued a statement about the incident, saying: “The safety of our students at Sam Houston High School and of all our schools is always our absolute top priority. The HISD police department and the school’s administration are continuing their investigations of what led to the detainment of a female student yesterday.”

The Perez family has indicated that the sophomore will no longer attend Sam Houston High.

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