ATLANTA (AP) - A former Atlanta police officer has pleaded guilty to aggravated assault of an unarmed teenager.

Fulton County District Attorney Paul Howard said in a news release Wednesday that 33-year-old Matthew Johns pleaded guilty Wednesday to charges including aggravated assault. He's set to be sentenced July 29.

Howard says officers were chasing a suspected stolen vehicle in September 2016, when a state trooper got it to stop. A 15-year-old passenger exited the car and lay on the ground with his hands up.

Howard says that despite the teen's surrender, Johns ran toward the boy, kicked him in the head three times and pressed his knee into the teen's neck. The teen became unconscious and suffered several injuries.

Johns, a nine-year veteran of the Atlanta Police Department, was fired in July 2017.

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