HMRC have provided a leaflet on Revenue fraud.
"HMRC works closely with the accountancy profession through various forums. The benefit of working with accountants, agents, tax advisors etc. is that they are able to amplify HMRC messages. They are also in a unique position of seeing first-hand how their clients structure and administer their business.
As part of the educational role that HMRC carry out we felt it would be useful for people to understand what some of the key fraud indicators (non-exhaustive) might be and the steps we would expect legitimate businesses to take to avoid being unwittingly caught up in the fraud. We have therefore produced the attached leaflet which we would ask you to host on your website or otherwise communicate to your clients.
We would be grateful for any feedback on the document, its value and what kind of issues you would like us to cover in any future updates.
Please feel free to feedback any comments to jane.hassan [at] hmrc.gsi.gov.uk"