Same thing happened to me a couple of years ago. The police chopper was circling around first telling everybody to be on the lookout for a pair that robbed one the local corner stores. Then they told everybody to get inside. The last thing I saw before closing the blinds was a cop strolling around out front with his sidearm out.
I lived in a first floor corner apartment at the time. I closed all the doors and windows, and hunkered down on the living room floor with a newpaper and waited it out (the lower half of the exterior wall was brick and the living room had the most barriers between myself and any stray bullets).
About 10 minutes later I hear Pop...POP...POP POP POP POP POP POP POP POP coming from the north. About 2 minutes after that, it came from the east. I kinda doubt the two robbers got to stand in front of a judge, at least not the mortal kind.
EDIT
you might consider a codeword or pair of codewords that require immediate compliance without question...do it, and I'll explain later
"safehaven" .... secure the home
"armed safehaven"...arm yourself, possible danger from intruder
"flee safehaven to ......"...leave immediately, take firearm,I'll meet you at a predetermined location
Dumb question, but why overcomplicate things? What part of "get and gun and..." does not connotate that the S is about to HTF and immediate compliance is required?
I can understand it as part of a school or other potentially high loss of life situation, but not at home.