MINNEAPOLIS (WCCO) — The Minneapolis NAACP is calling for changes to law enforcement practices following the arrest of a black man on the light rail last Wednesday.

Video surfaced of 21-year-old Draon Armstrong being slammed to the ground during his arrest on the Green Line at Target Field Station on July 8.

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Armstrong did not pay the $1.75 fare to ride, and Metro Transit police say Armstrong was not compliant with police.

But Armstrong says Thursday he never resisted arrest and believes the officer used unnecessary force.

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“Once I showed the doctor that video, he told me, ‘This dude could’ve took your life, he could’ve easily knocked you out from throwing you head first to the ground,'” Armstrong said. “He put [his] knee on my face, that’s embarrassing.”

The Minneapolis NAACP says it wants an open investigation into the incident.

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Metro Transit Police Chief John Harrington says he is open to having an investigation but he wanted to talk first to Armstrong and his family. Harrington says they have declined.