Two people are recovering from injuries as Chicago police search for the gunman.
The shooting happened around 11 a.m. at Roosevelt and State, near the busy Roosevelt CTA station.
Chicago police arrived on the scene just after 11 a.m. The busy block of Roosevelt between State Street and Michigan Avenue became a crime scene.
Chicago police say the two male shooting victims suffered minor graze wounds.
"It's 12 o'clock, noon, you hear gunshots around a train station," said Jabare Nichols. "It's crazy."
Some witnesses had just come out of the Roosevelt station to see the commotion.
"As I was coming out I actually saw a lot of police coming to see what was going on," said Erika Degraffinreaidt. "And I just looked back 20 minutes later, the tape was lying out, there were a lot of people around, so it sounded pretty serious to me." "It's unbelievable," said John Jasper. "I'm just glad it didn't happen during rush hour, when there's tons and tons of people out here."
The Jersey Mike's franchise opened in February on Roosevelt near State to capitalize on the area's high foot traffic. Franchise owner Len Foresta says they are prepared if they need to take extra security precautions, but Friday, he says, they didn't need to.
"There's two rival gangs we know of in the area," said Foresta. "With a lot of transient people using the el, using the bus service around here, we knew that there would be some risk involved, but it's an up-and-coming neighborhood."
Police are continuing to investigate. It remains unclear who fired the gunshots or from where the shots were fired.