Nafiysh Knox-Schenck, 32, was arrested on a warrant for alleged Violations of the Uniform Firearms Act, PPD said. A gun was recovered during his arrest, according to officials.
After he was placed in a police car on West Collum Street, an "unknown person" opened the door and he escaped, the department said.
Knox-Schenck fled east on Collum Street on foot, according to police.
Anyone who spots him should call 911, they added.
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