The Office of Fair Trading (OFT) has issued a warning about a telephone scam that is doing the rounds which involves fraudsters calling up claiming they’re from the OFT, saying that they can help the recipient claim back their bank charges.
The callers ask for both personal and financial details, including bank information, and the information is then used for identity theft and to obtain goods.
My advice is to be very wary of calls like this that come out of the blue, and particularly where you get asked to provide such details. You should not really be giving out such information over the phone or even in emails. If in doubt, ask for a number you can call them back on, see how it is answered and try to verify with the company they claim to be calling from that this sort of activity is going on.