The teen boy is facing first-degree murder charges, Snelling said, and investigators are still searching for a second suspect.
"In a brazen and senseless act of violence, Larry's life was taken from him by the very people he committed his life to helping," Snelling said. "We need to get a better message to our young people that this type of behavior is not only unacceptable, but it's deplorable."
Chicago's top cop, County State's Attorney Kim Foxx and other city leaders made that announcement at CPD headquarters.
Teen charged in shooting death of retired officer, CPD announces
"Based on the evidence that was presented in this case, we believed that act that was committed that day and that time was done with the knowledge that it would cause death," Foxx said.
CPD Chief of Detectives Antoinette Ursitti said retired Chicago Police Officer Larry Neuman, 73, was outside his West Garfield Park home on Thursday afternoon, paying a worker who was cutting his grass, when he saw two people with guns approach.
Neuman, seeing that the two offenders were armed, heroically pushed the worker out of the way, Ursitti said. Neuman then took his own firearm out of his waistband, and that's when the two suspects fired, striking him.
Neuman was able to fire at the suspects, who then fled on foot, Ursitti said.
It all unfolded around 1:27 p.m. in the 4300-block of West Monroe Street.
Ursitti said after police released surveillance video of the suspects on Saturday, investigators were able to identify the now-charged 16-year-old through anonymous tips and an officer who recognized him from a previous encounter in May, in which the teen was wearing the same clothes.
Video shows 2 suspects in murder of retired officer, CPD says: VIDEO
Ursitti said the 16-year-old turned himself in to the Area Four police station at Harrison and Kedzie on Sunday evening. He is being charged as an adult.
The late reverend's West Side community, including his fellow church members, gathered on Sunday where Neuman was fatally shot, honoring his legacy while calling for healing.
"This act of violence not only took a beloved husband, father, friend from his family, but it also robbed our community of a man who epitomized public service and dedication," Foxx said.
City leaders hope these charges can bring them some solace.
"We're reporting that we're bringing some type of justice to the family. It won't bring Larry back, but hopefully, we could stop another family from going through something like this," Snelling said. "What you see up here today is accountability."
Meanwhile, investigators are still looking for the second person allegedly involved in the shooting, and $75,000 total in rewards are being offered for information about Neuman's murder.
The rewards are being offered by the Chicago Police Memorial Foundation, ATF Chicago and FBI Chicago.
Anonymous tips can be submitted at CPDTip.com or by calling crime stoppers at 1-800-535-STOP.
The 16-year-old charged is expected to appear in court on Tuesday morning, just days before Neuman is laid to rest on Saturday.
Visitation for Neuman will be from 3 to 8 p.m. Friday at St. Michael Missionary Baptist Church, 4106 W. Monroe St., where Neuman was a member for 30 years as well as a pastor. Funeral services will be held at 10 a.m. Saturday at St. Michael.
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