Everyone has probably experienced the annoyance of being harassed by phone calls informing them they can claim a valuable gift or more worryingly received a subpoena from a local court.

The calls of course are traps, designed to con gullible people into parting with their money. Some elderly people have followed the instructions to remit cash into the swindlers' accounts, either because they could not resist the temptation of the promised gift or were afraid of getting into trouble.

But how do the swindlers get people's phone numbers? Some of them even have very detailed personal information such as addresses, identity card numbers, cellphone numbers and so on. At the thought of crooks discussing ways to make use of your personal information to make money, the hair at the back of your neck may stand up.