Announcement / panic alarm

I have read something about high priority announcements and wonder if that is the way to go for this:

I want to have a panic button on my colour touch screen. when you press it all the house lights come on. I also have the audio matrixer installed with an amplifier for each of 4 rooms. I would like the panic button to switch them all on and play a "Police have been called" announcement.

I have read that you can somehow get .wav files into the audio matrixer (?) to use for doorbell sounds, and wonder if instead i could record a voice as a wav saying that announcement and get it to play on endless loop until the panic button is un-pressed (with a password).

Any suggestions gratefully received.

thanks

nick