PHILADELPHIA (CBS) — For one police officer in Philadelphia’s 15th District, a report involving a 12-year-old boy armed with an assault rifle will be a call he’ll never forget.

Police say 19-year-old Michael Mitchell was armed with a handgun when he was arguing with his neighbor on the 2200 block of Kennedy Street over the weekend.

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During the altercation, police say Mitchell asked his 12-year-old brother to go grab an assault rifle.

Police say the boy is seen walking up his street with the loaded weapon. Then police arrive.

“I immediately confronted two males, one a juvenile and a second adult male,” said Officer Krzysztof Wrzesinski.

By then, police say both guns were inside a vehicle, but the teen allegedly tried grabbing the rifle.

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“I opened up the back door of the black Ford Taurus and he reached for the AR,” Wrzesinski said. “That’s when I yelled at him to ‘stop’ and he immediately stopped and complied.”

Neighbor Patrick Doyle captured some of the drama on camera, including the large police response. He’s glad the officer used restraint.

“After the fact, when I go home and sit down, the adrenaline goes down. I didn’t really think what to do, it’s just what we’re trained to do. It was the first time that happened to me on the job, which is a little bit of a shocker,” Wrzesinski said.

Credit: Philadelphia Police

Mitchell was charged with third-degree felony violation of the uniform firearms act- no license, first-degree misdemeanor criminal conspiracy, first-degree misdemeanor terroristic threats, first-degree misdemeanor violation of the uniform firearms -on street, first-degree misdemeanor corruption of minors, first-degree misdemeanor reckless endangerment of another person and violation of the uniform firearms.

Police say the 12-year-old was arrested. It’s unknown if any charges are pending.

In a tweet from the Philadelphia Police’s account on Monday, authorities sent this advice: “Parents: make sure your weapons are secured!”

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CBS3 has learned that Mitchell is the legal owner of the assault rifle.