NOT beating a dead horse, but everything I read says that the police protocol..

[dutch777]

6. We had an active shooter incident at our hospital and the police swept it immediately

They paired off as they arrived and had to get their long guns and vests from their car trunks, but they were in immediiately. Our security team drilled with them yearly in training exercises and the police were well versed in the layout of our large and complex facility. There was no shooting and the weapon reported turned out to be an umbrella tucked oddly into a backpack that one of our docs mistook for a gun. But was gratifying to see the police were as ready and willing as they could be to protect and defend.