The man was shot and taken to Advocate Illinois Masonic Medical Center in serious-to-critical condition, CFD said.
Chopper 7 was over the scene about 4:30 p.m., and there was a large police and fire presence near Clark Street and Fullerton Avenue.
Police were still on the scene some two hours after the shooting, on a popular stretch of restaurants, shops and salons in Lincoln Park.
Police said the 34-year-old man approached multiple people on the sidewalk before he was shot. Multiple witnesses told ABC7 the man who was shot had been roaming the block for much of the day, harassing and threatening people, hitting cars and acting erratically.
Around 4 p.m. witnesses said that man encountered another man who was armed.
"Starts screaming, yelling, pushing the guy, and he did it again, and then the guy came, took his gun out and shot him," said Aileen Nieves, a witness who works on the block. "Picked on the wrong person. He said, 'find out today,' and he found out."
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"Disconcerting to have this happen in the neighborhood, and you always think the North Side is so safe... but no, it's Chicago, and it can happen anywhere," Lincoln Park resident John Cutler.
The fire department said the man who was shot was hit twice. Witnesses told ABC7 he was shot in the chest, and the other man who was armed walked away calmly from the scene. It did not appear that he was arrested.
Witnesses also say that man who was shot at one point had been either ushered away or detained by police.
After those initial reports he'd been threatening people the man returned, and then the shooting happened.
Ald. Timmy Knudsen issued the following statement to residents:
"At approximately 4:30 PM this evening, a man was shot in the 43rd Ward near the intersection of Clark St and Fullerton Ave. According to initial reports, the victim was exhibiting erratic and dangerous behavior at the time of the shooting and engaged with the offender aggressively prior to the incident. The offender fled southbound on foot. The victim was brought to Advocate Illinois Masonic Hospital and remains in critical condition. There will be an increased police presence this evening in the area as officers canvas and patrol. There is reason to believe this is an isolated incident wherein the victim and offender had a preexisting relationship; however, it is currently being fully investigated by the 19th District Police and Area 3 Detectives. If you have any information that may be of use to the police, please call Area 3 Detectives at (312) 744-8261, email CAPS.019District@chicagopolice.org, or visit the "Chicago Police Tip Line" here. We will continue to update you on this situation if further information arises. Thank you to the Chicago Police Department, Chicago Fire Department, and other first responders who continue to keep us safe."
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