In message ,
Martin Underwood writes

I've heard that the failure of line-drop was a way that burglars prevented a
house's occupants from dialling 999 - they'd ring a number and then leave
their phone off-hook to keep the line open while they burgled the house.
Less reliable nowadays since many people have mobiles which could be used as
a fall-back in this case.

This was used for the old 999 diallers, and more recently digital
communicators hooked to the house line.

These days, anyone who needs any sort of security either has a dedicated
ICB line or Redcare.
--
Steve Fitzgerald has now left the building.
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