CBS 2's Jeremy Ross reports the suspects are still on the loose.
JEREMY ROSS: While drivers continue to use the ATMs in the area outside, the bank nearby has been closed down for hours now. That, of course, because of the gun violence that occurred outside and the investigation that followed.
- And we got a armored truck on scene. Six shots fired. Right outside the bank. No info on the shooter.
ISAAC LOPEZ: There were like 20 police officers, all the way around. Going crazy.
JEREMY ROSS: It is not the first time Isaac Lopez listened to the sounds of gun violence.
ISAAC LOPEZ: I heard the gunshots. It was like an automatic something. Pom-pom-pom-pom. Rapidly.
JEREMY ROSS: Just before 9:00 AM?
ISAAC LOPEZ: That's what got me by surprise. So early in the morning.
JEREMY ROSS: Police tape and squads made their way to this BMO Harris Bank at Lehman and North Avenue following the gunfire. Police say there, a security guard with a Garda armored truck, was emptying an ATM, when a dark colored SUV with two inside pulled up. At least one had a gun and demanded cash.
- There's definitely blood, so they're probably hit.
JEREMY ROSS: Investigators believe the security guard fired hitting one of the robbers. Both driving off, leaving a crime scene and a lasting impression.
ISAAC LOPEZ: Plain words it was stupid because how you going to rob the fully armor in an open space or there were desperate.
JEREMY ROSS: GardaWorld the company overseeing the trucks, confirming one of its armored vehicles was the target of a failed robbery attempt. Adding their employees are safe and were unharmed in the crime. Calling the actions of employees brave and vigilant, and thanking Chicago Police for their quick response.
ISAAC LOPEZ: I feel safe that the safety of the CPD, at least they're taking care of us here in Chicago. I'm supposed to go to the bank to take care of some stuff but I will have to leave it for Monday because their bank is closed right now.
JEREMY ROSS: No update from police at this point in time if anyone is in custody in connection with their ongoing investigation. GardaWorld adding that they are cooperating with law enforcement. In North Austin, Jeremy Ross, CBS2 News.