Beware of Clever Telephone Scam

We've had an increase in the number of reports of scams.
Please make yourself, friends, and family aware of a current telephone scam:

"I received a phone call from BT, saying that he was disconnecting me because of an unpaid bill.
He demanded payment immediately of £31.00 or it would cost £118.00 to re-connect at a later date.
The guy wasn't even fazed when I told him I was with Virgin Media. He said VM have to pay BT a percentage for line rental! I asked his name – he gave me the very 'English' John Peacock in a very 'African' accent – & phone number -0800 0800 152.
Obviously, the fellow could see I didn't believe him, so he offered to demonstrate that he was from BT. I asked how. He told me to hang up & try calling someone – he would disconnect my phone to prevent this.
When I attempted to call someone, my phone was dead – no engaged tone, nothing – until he phoned me again. Clearly pleased with himself, he asked if that was enough proof that he was with BT. I asked how the payment was to be made & he said credit card, there & then.
I said that I didn't know how he'd done it, but I had absolutely no intention of paying him. I didn't believe his name or that he worked for BT. He hung up. I dialled 1471, but the number was withheld I phoned his fictitious 0800 number – not recognized.
I phoned the police to let them know. I was one of many. It has only just started apparently, but it is escalating."
Please let as many people as possible know of this scam. The fact that the phone does go off would probably convince some people it's real, so please make as many friends & family aware of this.

How is it done? This is good but not that clever. He gave the wrong number – it should have been 0800 800 152 which takes you through to BT Business.

The cutting off of the line is very simple, he stays on the line with the mute button on and you can't dial out – but they can hear you trying.
This is because the person who initiates a call is the one to terminate it. When you stop trying he cuts off and immediately calls back. You could easily be convinced!
The sad thing is that it is so simple and it will certainly fool many. By the way, this is not about getting the cash as this would not get past merchant services – it is all about getting credit card details which include the security number, to be used for larger purchases.