phone calls making bomb treads, on not usual countries with armed guerrillas or paramilitary orgs, which use codes to validate the tread to the cops...are made, by making the phone call, to a media source, either newspapers, TV, radios, and not directly to the target; the other aspect is, tape the tread first, and release the record of the tape, on the phone call, do not use a direct speech, or they don't take you...seriouse!