CHICAGO (WLS) -- Video of a Chicago police officer shooting a man who allegedly was pointing a gun at him was released Wednesday.
The Civilian Office of Police Accountability, an independent agency that investigates CPD shootings, continues to investigate the shooting of 23-year-old Derrell Johnson.
The shooting occurred Halloween night as children were trick-or-treating in the city's East Chatham neighborhood on the South Side.
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Police said that Johnson is a suspected gang member and convicted felon who had a gun with metal-piercing bullets.
The bodycam video shows the officers' encounter with Johnson in a stairwell near 79th and Drexel.
The incident started a couple blocks away as police said plainclothes officers approached a group of people near 79th and Ingleside when a man who appeared to be armed ran from the scene.
Surveillance video from the neighborhood appears to show a foot pursuit which leads to the third-floor of an apartment building. When he enters, for a brief moment, the bodycam captures the suspect trying to escape through the front.
From there the chase enters that stairwell and then that gunfire.
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The officer's gun was drawn in pursuit of a suspect as he entered the stairwell. The cop opened fire as he continues racing down stairs.
Seconds later, the man being pursued is seen bleeding and dazed as the officer orders him to the floor.
As the officer handcuffs the man and secures the scene other officers arrive, including one who spots a weapon on another floor. After putting on gloves, he picks up the gun and brings it downstairs.
The video shows a clear image of the weapon and extended clip, which CPD said contained metal-piercing bullets.
Upstairs, the officers who fired his weapon called for paramedics.
"Get an ambulance. Get an ambulance. He got shot in the back. I shot him in the back," the officer can be heard saying in the video.
Johnson was taken to a hospital and later charged with multiple felonies, including aggravated assault to an officer. At the time of the shooting nine weeks ago, Johnson was on parole following a string of felony convictions.
Video of Chicago officer shooting man allegedly armed with gun released