The violent outburst came just hours after the department announced a sharp decrease in crime on Friday.
Data collected by the Chicago Police Department showed a 13% decrease in shootings and a 7% decrease in murders, year-over-year, during the first five months of this year.

"Chicago residents and visitors can be confident that CPD works day and night to keep them safe," Police Superintendent Eddie Johnson told the Chicago Sun-Times on Saturday. "Of course we can always do better, but I believe that our officers work diligently to provide consistent and fair policing in all of our neighborhoods, and our efforts are paying dividends."
Police said 41 people were shot and seven were killed in the city during the previous weekend, according to the Sun-Times.
ABC News' Alexandra Svokos contributed to this report.