The statement from Floyd County Sheriff Tim Burkhalter says Cpl. Christopher Parton was fired for conduct unbecoming an officer when he was taking a 20-year-old suspect to jail in June.
The sheriff's statement says Parton's actions during the arrest can't be tolerated, but it doesn't say just what Parton did. News outlets say the details remain unclear.
Chief Deputy Tommy McGuire says other deputies also are being investigated over the same incident. Authorities haven't identified them.
Parton was transporting Eric Jermaine Montgomery Jr. to jail at the time. Montgomery remains in custody on charges including cruelty to children and willful obstruction of law enforcement officers.
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