Cell phone video shared by CWB Chicago showed the suspect kneeling on the ground, stuffing money into a bag before fleeing the bank. Money can be seen blowing in the wind.
Chicago police said as the suspect left, he was confronted by a security guard, and there was an exchange of gunfire.
New video obtained by ABC7 Eyewitness News from a CMEA Group employee shows the suspect calmly gathering cash into a bag after apparently shooting out the revolving door windows, then rounding the corner calmly and heading east on Madison Street.
A bullet grazed the 59-year-old security guard during the incident.
The FBI released a surveillance photo and description of the suspect, describing him as a male, 5-feet, 7 inches tall with a medium build, wearing a black hooded jacket, a mask, winter gloves and blue jeans.
The robbery took place about 3 p.m. at the Fifth Third Bank near Wacker Drive and Madison Street.
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Some witnesses heard the gunshots.
"I texted my mom, and I was like, 'mom, I think someone just got shot downstairs,'" Abby Gasick said. "I work right next to the window, and we heard a bunch of loud gunshots."
The security guard is expected to be OK. He was treated at the scene.
Chicago police briefly shut down Ogilvie Transportation Center at 500 W. Madison to search for the suspect, but did not find him.
No one is in custody, law enforcement said.
Fifth Third Bank released a statement, saying, "We are not able to speak to the details of the incident, but the safety of our employees, customers and the public is our utmost concern. We are cooperating fully with law enforcement authorities."
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