It could be any number of ways, do you shred all your rubbish with any bank details on?
It could be from bank statements, receipts, all kinds of things if you've thrown them away. Buy a shredder and shred anything with any personal details on.
Mail could have been stolen or being delivered to an old address etc... If this may the case try here to get it redirected...
http://www.royalmail.com/
You can get a protective entry put on to try and prevent this happening in the future, try here...
http://www.cifas.org.uk/
This site also has a great deal of other useful info.
You can also check your credit rating here...
Obtain a copy of your credit file from the following credit reference agencies, it costs as little as �2:
Call Credit �
http://www.callcredit.plc.uk/
Equifax �
http://www.equifax.co.uk/
Experian �
http://www.experian.co.uk/
You can also report it to the police...
http://www.police.uk.
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