My dp has just given me an email that he received at work warning him of a telephone scam the email was off the police). TO keep this short first you get a call telling you that you've won an all expenses paid trip to an exotic destination. Please press 9 now to hear futher details.
Then if you press 9 you will be connected to a premium rate line that bills in the region of £20 per minute. Even if you disconnect after you've pressed 9 the other end will stay connected for a minimum of 5 minutes. This will cost you around £100 and lasts for 11 minutes. The final part of the call asks you to key in your postcode. Then respondes with a message saying "sorry you are not one of the lucky winners". Thereafter disconnecting you adding another £260 to your bill.
These calls are originating from outside the UK and BT and other telephone companies are relatively powerless to act. The safe solution is to hang up befor the message asks you to press 9.