From this web site you can report all instances of fraud anonymously

There are many sorts of fraud including plastic card fraud, identity theft, insurance and benefit fraud. Most of the information on this site is about benefit and insurance fraud, but there is some information about identity theft, scams and internet fraud and you will find links to other sites containing information on the various types of fraud we have outlined.

Fraud damages the economy

Fraud overall costs the British economy an enormous amount of money, estimated as at least £14 billion in a report commissioned by the Association of Chief Police Officers (ACPO) published in March 2007.    The costs of fraud impact throughout the economy. Fraud drives up costs for consumers (for example through increased insurance premiums) and reduces the amount of money available for public services (because fraudsters claim benefits that they are not entitled to, which leaves less available for public spending).

Benefit Fraud Statistics