Police and credit card companies have issued a warning about a new form of scam, which has been reported not only in Britain but all over the world.

What makes this scam particularly dangerous is the scammer already knows the credit card number and instead attempts to convince the owner to reveal the three digit security code on the back of the card.

According to reports from various parts of the country, holders of Visa and Mastercard accounts have been targeted by the crooks using telephone messages purporting to be from the banks.

Keep you details safe

The tricksters display knowledge of the account by reading out the sixteen digit account number on the front of the card.

The person on the phone will then ask customers to confirm a suspicious payment, usually between £297 and £497, which they say come from a company they have been tracking as suspicious. The fraudsters, still acting under the guise of a genuine Visa or Mastercard representative will claim to be debiting your account.

Relying on the temporary relief of the customer that a 'suspicious' purchase has been cancelled the crooks will then ask for the security code in order to 'confirm you are in physical possession of the card'.

The scam has been seen far and wide throughout the world including German, America and Canada but police are still unsure as to the source of the fraud.

Cathy Skutovich from Canadian bank Windsor TD, commenting on the practice noted that this seemed to be an extremely organised group and that their operation was “pretty slick.

“What's different with this scam is they already have your card number, the one thing they're looking for is the security code on the back. I'd hate to see people being victimized. I'm amazed at how trustworthy some of our clients are, giving out information they shouldn't,” she added.

There have also been similar cases reported in the US, with scammers attempting to convince cardholders to type in their personal card numbers over the phone.

“I got a recording that said it was Chief Financial calling. My credit card had been temporarily suspended. They had suspected fraudulent use, and that if I wanted to talk to one of their security specialists to hold on the line,” said Connecticut resident Sheri Dejesus

“They continually asked me about four or five times to put in my 16-digit card number, which obviously I didn't do, I just hung up,” she added.

“People will never get a call from us asking for their security details. If they do, they should report it immediately to their card issuer,” said a Visa spokesman.