STORY YOUMISSED
A late-night altercation turned tragic in the 19th District on Chicago’s North Side earlier this month.
The violent incident occurred at approximately 11:56 p.m. on October 2, 2026, in the 800 block of West Wellington Avenue.
A 51-year-old male victim was severely battered during a physical assault on the street.
The brutal attack inflicted severe physical trauma on the 51-year-old victim.
The victim subsequently died from the traumatic injuries he suffered during the altercation.
Chicago police detectives launched a thorough investigation to identify all individuals involved in the physical assault.
Area detectives gathered evidence and identified 35-year-old Mateusz Mysliwiec as a primary participant in the fatal attack.
Mysliwiec resided in the 6400 block of West Belle Plaines Avenue in Chicago.
Records show Mysliwiec had a prior criminal record in Chicago dating back to 2014.
His previous arrests included charges for simple assault, criminal damage to property, battery of an unborn child, aggravated assault with a deadly weapon, and an outstanding warrant.
Officers located Mysliwiec on Sunday, October 11, 2026, in the 2900 block of North Central Avenue.
CPD personnel took Mysliwiec into custody without further incident at the scene.
Law enforcement personnel transported Mysliwiec to police headquarters for official processing and charging.
Cook County prosecutors officially charged Mysliwiec with one felony count of first-degree murder.
Mysliwiec appears at the 2600 South California courthouse on Wednesday, October 14, 2026, for a formal detention hearing.
Prior Arrest History
Chicago Police Department booking records reveal Mysliwiec has a extensive history of prior arrests across multiple city districts:
March 2, 2014: Arrested in the 016th District (8420 W. Windsor Ave.) and charged with simple assault and criminal damage to property under $300.
August 30, 2018: Arrested in the 025th District (5931 W. Belmont Ave.) and charged with driving on a suspended license, negligent driving, and illegal transportation of alcohol by a driver.
April 18, 2023: Arrested in the 016th District (6400 W. Belle Plaine Ave.) and charged with battery (physical contact) and battery of an unborn child.
October 23, 2025: Arrested and charged with criminal damage to property under $500 following an incident in the 6616 block of West Montrose Avenue.
May 21, 2026: Arrested in the 016th District (6343 W. Irving Park Rd.) on an outstanding warrant.
July 5, 2026: Arrested in the 016th District (5151 N. Milwaukee Ave.) and charged with aggravated assault with a deadly weapon and possession of replica firearms/pellet guns.
