> How often do we hear about bombings where the bombers broadcast an evacuation message on a loudspeaker for 15 minutes prior to the explosion? This is how the

> How often do we hear about bombings where the bombers broadcast an evacuation message on a loudspeaker for 15 minutes prior to the explosion? This is how the Provisional Irish Republican Army operated, at least some of the time. For instance they telephoned in warnings 90 minutes before the 1996 Manchester bombing (1500 kg bomb, 212 injuries and no fatalities.) I've read somewhere they had established codewords with British authorities so those authorities knew which warnings to take seriously.