RAPID CITY, S.D. (AP) — One of the newest members of the Rapid City police force is the brother of an officer killed in the line of duty four years ago.

Mackenzie Armstrong was among 11 new officers sworn in during a Wednesday ceremony. He's the brother of Nick Armstrong, who was killed in August 2011.

Mackenzie Armstrong says being a police officer "is a dream come true." And he says he believes his brother would be proud of him.

Nick Armstrong and fellow Officer Ryan McCandless were shot and killed during a confrontation with a man who also died in the exchange of gunfire. A third officer, Tim Doyle, was wounded but later returned to work. He attended the swearing-in ceremony.

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