CHICAGO (CBS) — Des Plaines police were the ones who accidentally shot a 15-year-old boy on Tuesday night while going after a bank robber who had shot a Chicago Police officer.

The incident happened at the UpBeat Music & Arts school at 4318 W. Irving Park Rd.

The bank robber – identified as Christopher Terrell Willis, 32 – had held up a bank in Des Plaines and stolen a white Buick, in which he had led police on a chase all the way down the Kennedy Expressway to Irving Park Road near Kildare Avenue.

A TIMELINE: From Bank Robbery In Des Plaines To Melee Of Gunfire In Old Irving Park

Police said Willis shot a CPD officer in the side of the head upon being confronted by police on Irving Park Road, and then ran into the music school. Des Plaines police shot and killed him in a gun battle inside the music school.

The gunfire in the music school wounded the 15-year-old boy, a student at Lane Tech. Police initially said he was there taking a piano lesson, but it was later clarified that he was working the front desk at the music school.

As CBS 2 Investigator Megan Hickey reported, the UpBeat Music & Arts school was closed with the lights off on Wednesday evening.

Meanwhile, when CBS 2 pressed Des Plaines police about the details of the gun battle, they said they couldn’t comment. But then, Chicago Police did.

“Shooting that 15-year-old boy was a horrible tragedy, horrible. Thank God it didn’t turn out worse than it did,” said Chicago Police First Deputy Supt. Anthony Riccio. “But yeah, we absolutely had to go in there and get him.

Chicago Police said Wednesday afternoon it was a Des Plaines officer who shot the boy, while firing at the suspect, who did not fire any shots while inside the music school.

“There is no indication that inside the music store that the 32 year old suspect was able to get off a shot,” Riccio said.

Chicago Police also said Des Plaines police followed protocol when they pursued the bank robbery suspect out of their jurisdiction, onto the expressway, and then into the Old Irving Park neighborhood.

“I don’t know what Des Plaines’ training is, obviously, but I would say this, we have a guy that’s armed with a handgun running into an open business that’s occupied with customers, employees. We know that he’s already robbed a bank. We know that’s he committed an armed carjacking. We know that he shot a police officer,” Riccio said. “I think we absolutely have to pursue him inside there and do whatever we can to neutralize him.”

We wanted to check for ourselves. But on Wednesday, when Hickey asked the Des Plaines police chief for a copy of their department’s police chase policy. The chief he said he couldn’t give it to her and she would have to file a formal Freedom of Information Act request.

They were the only department to fire their weapons at 32-year-old Christopher Terrell Willis after he exited the stolen white Buick that he was driving and started firing shots.

The boy was taken to Lurie Children’s Hospital in critical condition. Mayor Lori Lightfoot said she has visited with his parents, and his condition has stabilized.

“He was having surgery. All indications are that, after a lengthy surgery, he is in stable condition,” Lightfoot said. “It’s obviously impossible for me not to think about his condition, and the trauma to his family, in light of my own status as a mother, and just as a person who cares about what happens in this city.”

The wounded officer remained in the intensive care unit Wednesday morning at Advocate Illinois Masonic Medical Center. Lightfoot said he was in serious but stable condition. Police said he’ll likely remain in ICU another 24 to 36 hours. Police have not released the officer’s identity, but said he’s been on the force for 17 years, and has been decorated with more than 100 commendations for his service.

The Gunman’s Criminal Background
Meanwhile, we’ve also learned more about bank robber and gunman Willis. It wasn’t the first time he’s been accused of attempted armed robbery, and it’s also not the first time he’s tried to carjack someone at gunpoint.

At the time of the robbery, Willis was apparently looking for a quick money grab.

His landlord, who did not want to be identified, told CBS 2’s Charlie De Mar that Willis was often short on cash – failing to pay rent.

“When it came down to I guess needing money or whatever, he didn’t really have a lot of ways of making it other than apparently these illicit ways,” the landlord said.

Willis and a woman he lived with were evicted from their South Side apartment in recent weeks. Willis was also arrested at that same apartment for in July for domestic battery.

“The SWAT team came and arrested him,” the landlord said. “They had domestic problems and he wouldn’t move out.”

The suspected bank robber’s criminal history goes all the way back to 2002, when he was charged with armed robbery and carjacking as a teenager.

CBS 2’s Hickey and her crew was the first on the scene in the Tuesday night incident in Old Irving Park. Willis sped by their live truck Tuesday night on the Kennedy Expressway.

He was driving recklessly on the shoulder, followed by at least a dozen squad cars.