"This is a very difficult time for the Chicago Police Department," Brown said. "We're heartbroken."
WATCH: CPD update on officer killed in Gage Park
Chicago police update on CPD officer killed in Gage Park shooting
Chicago Police Superintendent David Brown said the officer was responding to a domestic violence 911 call about a person with a gun in the 5200-block of South Spaulding at about 4:45 p.m.
The caller told police a man was chasing a woman down the street with a gun, Brown said. Two two-officer cars responded to the scene. One set of officers knocked on the door of the home, while the other set of officers began talking to the suspect.
CPD officer was responding to domestic call when fatally shot
The suspect ran from officers, still with the gun. The officers gave chase and the officer who died and the suspect exchanged gunfire at close range, Brown said.
The officer was struck multiple times and taken to Mt. Sinai Hospital in critical condition, where he succumbed to his injuries.
WATCH: Body of fallen police officer arrives at Medical Examiner's office
Body of fallen CPD officer arrives at Medical Examiner's office
The suspect was also shot in the head and is currently hospitalized in critical condition.
Brown said the officer had been with the department for five years and has a family of public servants. No further details about the officer have been released.
Hundreds of officers of every rank and nearby department converged on the hospital to form an emotional and physical backstop. They stood at attention, saluting the life and service of the officer as his body was loaded into an ambulance.
Even more officers lined the streets as a procession escorted the fallen officer's body from the hospital the Cook County Medical Examiner's Office.
The suspect is 18 years old and does not have an extensive criminal history, Brown said.
Chicago mayoral candidate Paul Vallas released a statement, saying in part, "The courageous men and women of the Chicago police department have suffered another tragic loss of one of their own to the ultimate sacrifice of protecting our communities. My heartfelt thoughts are with the officer's loved ones and the entire CPD family who are grieving during this difficult time."
Chicago mayoral candidate Brandon Johnson released a statement, saying, "This is a sad and sorrowful day for our city, and my heart goes out to the family, friends and colleagues of the Chicago police officer whose life was taken in the line of duty in Gage Park this afternoon. I am praying for healing for all those close as we await further details on this tragedy."
The last Chicago police officer who was shot and killed in the line of duty was Ofc. Ella French.
"I ask that this city cover this officer's family. This is a family of public servants and as you can imagine, they are taking this tragedy, very, very hard," Brown said.
The Civilian Office of Police Accountability will be conducting an investigation into the police shooting. Brown said body-worn camera footage is being reviewed.
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