Q75: A house/business burglar alarm is going off, what can I do?
If you hear an alarm sounding and there is evidence of ongoing criminal activity you should dial 999. It is not advisable to put yourself in any danger by making the checks yourself.
If it appears to be a false activation, still contact the police but on their non-emergency number as they may have the owners contact details on their database. If it is a persistent problem see the question in related information about noisy neighbours.