Police said an on-duty Chicago police officer was sitting in his unmarked car at about 5:30 p.m. in the 600-block of West Chicago Avenue when a man approached him and demanded his car at gunpoint.
Police said suspect took off in the unmarked police car and drove to the Near North Side where he attempted to carjack another man sitting in a vehicle at Rush and Oak. When the man refused to give up his car, the suspect shot him in the arm, according to police.
"I hear the biggest bang. It echoes throughout the buildings. I look, I see someone running away from a black Nissan," said witness Normal Morris.
The man was taken to Northwestern Memorial Hospital for treatment of non-life threatening injuries.
"You didn't know what, exactly, what was going on, how many other shooters were in the vicinity," Morris said.
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According to police, the suspect then carjacked a dark-colored Jeep and fled north on Inner Lake Shore Drive. He abandoned the car in the 1400-block of Inner Lake Shore Drive.
The suspect then tried to carjack another man, who also refused to give up his vehicle. Police said the suspect shot that driver, who suffered a graze wound.
"He said if he hadn't ducked the bullet would have hit him in the head," said Michell Klarcheck, wife of the second victim.
Police said the suspect then approached more drivers, trying to carjack more vehicles, before running into a nearby condo building where officers arrested him.
Police said they recovered a semi-automatic pistol.
"I've been working downtown since 2006. I take this very personally," said Dep. Chief Kevin Ryan, Chicago Police Department. "We are not going to let people come down here and do this."
Police have not released any information about the suspect in custody other than to say he has a criminal record.
Inner Lake Shore Drive was closed briefly for the investigation.
Chopper 7HD over a carjacking, shooting at Oak and Rush