The shooting took place near Western and Rosemont avenues in West Rogers Park about 3:25 p.m., officials said.
The cameras from an auto shop captured the moment one of the victims ran inside. The owner says he believes he was running for his life before he collapsed in the front of his shop.
A 31-year-old man and a 24-year-old man were on the sidewalk when they were shot by an unknown suspect, Chicago police said.
The 31-year-old was shot in the back and taken to St. Francis Hospital in critical condition, police said.
The 24-year-old was shot in the abdomen and taken to the hospital in fair condition, CPD said.
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Chopper 7 was over the scene just before 5 p.m.
Chicago police and crime scene tape could be seen in front of an auto repair business.
Surveillance video showed two people running in a back alley before one person runs into the West Rogers Park auto shop off Western and Rosemont. The video shows the shop's owner, Aamir Khan, as the man walks by him.
"He ran from the alley and he saw my door was open," Khan said.
It happened after Khan and his employees heard about four loud gun shots outside.
"I was standing right by my in front of my office," Khan said. "He just come right in front of me. I got a little like, you know, worried and scared that maybe he had a gun, but because I heard the shot."
Khan said the man appeared to have at least one gunshot wound.
"We went into the office, locked the door. I thought maybe somebody was chasing him, you know? And then, then I called 911," Khan said. "I talked to the police, they say it was a rifle. They had rifles."
Area Three detectives are investigating.
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