Arizona cop punches a 15-year-old girl in the face

An was filmed punching a 15-year-old girl and then pinned her to the ground.

An officer in Mesa, Arizona was filmed as she punched a 15-year-old girl and then pinned her to the ground.

"I can't breathe," the girl can be heard yelling over and over again as someone who is identified as the girl's mother can be seen talking to the cops, apparently begging the officer to let her go.

The Free Thought Project, which linked to the video, says the girl's mother "attempted to explain to the officers that she has mental problems as well as asthma." The person who posted the video on Facebook on Friday-Luis Paul Santiago-says the girl was a runaway and "emotionally unstable." She also apparently suffers from asthma.

Santiago described the scene in a comment to the video:

Santiago says the police tried to delete the video off his phone. And when he told a second officer at the scene what he witnessed, "the cop said the female cop acted correctly and if she needed to she can shoot her dead."

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- Slate