Photo: Adrian S. Burrows Sr./NBC/NBCU Photo Bank via Getty Images

Alberto Rosende, Miranda Rae Mayo

Chicago Fireis taking a brief hiatus.

The NBC drama stopped filming immediately after gunfire was exchanged close to the set,Varietyfirst reported.

The incident is currently under investigation, and no one is in custody.

TheChicago Fireset 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

Miranda Rae Mayo as Stella Kidd, Taylor Kinney as Kelly Severide - CHICAGO FIRE – “The Magnificent City of Chicago” Episode 1022

Chicago Fireis 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).

There were a few surprise guests at Kelly and Stella’s wedding fromChicago Firepast. But thebiggestwas Matt Casey (Jesse Spencer), who served as Kelly’s best man.

“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 Fireco-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 ofChicago Firewill air new episodes each Wednesday at 9 p.m. ET on NBC.

source: people.com