Adrian S. Burrows Sr./NBC/NBCU Photo Bank via Getty Images
Chicago Fire is taking a brief hiatus.
The NBC drama stopped filming immediately after gunfire was exchanged close to the set, Variety first reported.
The Chicago Police Department confirmed to PEOPLE that a gunman fired shots around 1:45 p.m on Wednesday near the 5900 block of W. Madison St. in Oak Park, Ill. The suspect then fled the scene in a black SUV. No one was struck by the gunfire.
The incident is currently under investigation, and no one is in custody.
The Chicago Fire set promptly entered into security protocol on Wednesday and halted production after shots were heard. According to a source close to the series, no one connected to the production was involved or injured.
Filming will resume Thursday.
Adrian S. Burrows Sr./NBC
Chicago Fire is gearing up for the premiere of its 11th season on Sept. 21. It will pick up where season 10 left off — in the aftermath of Kelly Severide's (Taylor Kinney) wedding to Stella Kidd (Miranda Rae Mayo).
Per a synopsis for the season 11 premiere episode, "Kidd and Severide's honeymoon is interrupted by a dangerous person from their past" and "Kidd's former academy classmate joins Firehouse 51."
"Jesse Spencer so understands the character — and especially the relationship that Casey has with Severide, the bond of that friendship — and he knew the character had promised to be there at the wedding as the Best Man," Chicago Fire co-showrunner Andrea Newman told PEOPLE of the decision to bring Spencer back.
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"Jesse is just like Casey: he's a man of his word and he was going to make it happen," she added. "He is completely connected to the character in that way."
Season 11 of Chicago Fire will air new episodes each Wednesday at 9 p.m. ET on NBC.