Thanks for the coastguard suggestion - did think of the police but must confess that wasn't certain that with the very vague information I had it would have been beneficial. "Distress flares sir? What exactly do you mean?" was the kind of response I'd expect from non nautical and aviation fields - I could be being terribly unfair on the emergency services operators by saying that, however.
SH - thanks very much for your help.
Paul.