The teen was taken in critical condition to Advocate Christ Medical Center in Oak Lawn where he died.
"They just killed him for no reason. They don't know who they killed. A father. The father of a seven-month old child who will never know her father," said Aja Daily, friend.
A weapon was recovered, and no other injuries were reported.
The Cook County Medial Examiner's Office identified the teen as 16-year-old Martinez Winford of Chicago.
Police said the Independent Police Review Authority is investigating.
The Associated Press contriuted to this report.