CHICAGO (CBS) — Chicago police were looking into the authenticity of cell phone video recorded by a witness of a fatal police-involved shooting in Mount Greenwood, after images from the video appeared to show the man who was shot pointing a gun.

Police also were canvassing the neighborhood for private video from businesses in the area, and asking people who might have been walking or driving nearby at the time if they have any photos or video of the incident.

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Joshua Beal, 25, was shot and killed after a brawl outside a Chicago fire station near 111th and Troy, while he and his family were part of a funeral procession.

A witness to the shooting recorded video of the incident on a cell phone. Images from the video show a plainclothes officer pointing his gun in the street. It also shows a young black man pointing a gun towards officers. Police said the images appear to be the suspect.

Cell phone video from a witness to a fatal police-involved shooting in Mount Greenwood appears to show the suspect pointing a gun. (Supplied to CBS)

Cell phone video from a witness to a fatal police-involved shooting in Mount Greenwood appears to show the suspect pointing a gun. (Supplied to CBS)

“We received this same photograph today and we are currently analyzing it to determine its authenticity and origin. While it appears to be the offender, we cannot say for certain until the analysis is complete,” Police spokesman Anthony Guglielmi said in an email.

Police said, around 3 p.m. Saturday, a car stopped in front of the firehouse, and an off-duty firefighter told the driver they were illegally blocking a fire lane. The people in the car then got out and got into a verbal and physical altercation with the firefighter, according to police.

“An off-duty police officer who was in an establishment, a barber shop, across the street, and he observed the physical altercation. He also came out and became involved in the physical altercation, announcing his office,” Chicago Police Supt. Eddie Johnson said.

Police said a uniformed police sergeant who was driving to work at the Morgan Park District station pulled up and saw a man with a gun in his hand, so he got out of his car and announced his office. The sergeant pulled his weapon, and when the man with the gun did not drop his weapon, shots were fired, and the man was shot several times, according to police. Police have not specified who fired the shots.

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The man, identified by his family as 25-year-old Josha Beal, was taken to Advocate Christ Medical Center in Oak Lawn, where he was later pronounced dead.

Joshua Beal (Photo supplied to CBS)

Joshua Beal (Photo supplied to CBS)

Beal’s family disputed the police version of what happened. His mother, Tiffany Boxley, said her son was visiting Chicago for a funeral when police shot him during the procession on 111th Street. She said an off-duty firefighter rammed the family’s car, sparking an argument.

“Chicago police gunned my baby down like a vicious animal,” she said.

Beal’s sister, Cordney Boxley, said the officer who came out of the barber shop never announced himself as police.

“My brother is one who is licensed to carry his gun wherever he goes. This man never identified himself, never said anything. He just started shooting through the windshield of my brother’s car,” she said.

A witness recorded video of part of the incident on her cell phone. Video shows a plainclothes officer pointing his gun in the street. It also appears to show Beal holding a gun. Although the video does not show what happened when shots were fired, it did capture the sound of several gunshots.

Police said numerous people suffered non-life-threatening injuries, including the off-duty firefighter and off-duty police officer. The sergeant was not hurt.

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The Independent Police Review Authority was investigating. The officers involved were placed on administrative duties for 30 days while the shooting is under investigation.