The part that surprises me here is that the security guard was allowed to carry an AR-15 or any other long gun. When I worked in the industry, handguns were pretty much the only firearm allowed at most companies with armed guards (not including armored car and other specialized security firms, which were a bit of a different business altogether)
Either way, could to see the thugs were thwarted. It would have been better had they’d gotten tagged, but at least the security guard was able to protect his charges.
See the way the guy in the top image is holding that weapon?