Stolen: If you see this Fort Lo-Pro...

Bull shit. They'll turn up in a couple of weeks if you're lucky. The best chance you have via tha po po is tell them someone has pulled a knife on you or you suspect there's a gun at hand.

A tactic I have used a couple of times is to say "you better get here quick cos I'm gonna kill the cunt". I have meant it on both occasions but the OB were there in a flash.