Police investigators said Joshua Beal of Indianapolis was carrying a firearm when he was fatally shot on Saturday, but family members dispute the police narrative, WLS reports. A spokesman for the Chicago Police Department said the officer was fired on and returned fire.
"Nobody should have to sit there and witness their brother get killed by the same people who are supposed to protect us," said Beal's sister Cordney Boxley.
The victim was identified by family as Joshua Beal, a father of two. He was taken in critical condition to Advocate Christ Medical Center, where he died. He was in Chicago for a funeral
The shooting took place after a vehicle leaving funeral services at a nearby cemetery stopped in traffic in front of a Chicago fire house, police say. An off-duty firefighter told the driver that they were illegally blocking the fire lane. The occupants exited the vehicle and an altercation ensured, police said. An off-duty Chicago police officer inside a nearby business came out to assist the firefighter.
A Chicago police sergeant driving to work stopped when he observed a man with a firearm in his hands. After the man "failed to drop his weapon, shots were fired striking the individual multiple times," police said.
"Chicago police gunned my baby down like a vicious animal," said Tiffaney Boxley, Beal's mother. "They shot him twice in the back and three times in his front."
A woman who said she was driving by as the fight escalated recorded cellphone video that captured the sounds of multiple gunshots.
"The man didn't pull a gun," said the woman, who declined to be identified. "The man was on the passenger side of the car."
The off-duty police officer and off-duty firefighter sustained non-life-threatening injuries.
The officers involved will be placed on routine administrative duties for 30 days, police said.
The Independent Police Review Authority is investigating.
ABC News' Brendan Rand contributed to this report.