They seem to run out of resources to pull off full-fledged FFs.

"An off-duty firefighter reportedly stopped a man armed with tactical weapons and 100 rounds of ammunition at a Walmart in Springfield, Missouri.

Officers responded to reports of an active shooter at the Walmart, which had been prompted by the man walking around the store with a shopping cart, body armor, and tactical weapon. A manager noticed the man, pulled a fire alarm to evacuate the building, and then contacted police. The man was then stopped by an off-duty firefighter at an emergency exit, who held him at gunpoint until police arrived.

Police stated that he suspect was a young white male, appearing to be in his twenties. They have not identified the man, but did confirm he had loaded weapons inside the store."

https://newsbreakinglive.com/2019/08/08/off-duty-firefighter-stops-armed-man-at-springfield-missouri-walmart/