Worried cheaters who are trying to find out whether their details appear in the Ashley Madison data dump should beware - some sites are tricking them into exposing themselves.

In the scramble to find out who is on the list of potential cheaters, some websites have been set up claiming to be searchable databases.

But e-mail addresses entered into them are then made publicly visible, showing that a worried cheater or suspicious partner has been checking the leaked information.

Other websites are signing people up with private investigators specialising in detecting infidelity when they enter their details - a breach of privacy that could be just as risky to someone as the original data leak.

Some people have also been encouraged to fill in lengthy online surveys to access the data, only to be handed fake or out of date user details.

Meanwhile, genuine websites which let users search for usernames and e-mail addresses are being forced offline by Ashley Madison, which is issuing copyright infringement threats.

They say that because the database was taken from their servers without their permission, anyone publishing it is in breach of copyright.

One site forced off the web turned on the site's developers, writing in a post: "To Ashley Madison's development team: You should be embarrassed for your train wreck of a database (and obviously security), not sanitising your phone numbers to your database is completely amateur, it's as if the entire site was made by Comp Sci 1XX students."

But in a statement Ashley Madison owner Avid Life Media said: "The criminal, or criminals, involved in this act have appointed themselves as the moral judge, juror, and executioner, seeing fit to impose a personal notion of virtue on all of society."

"We will not sit idly by and allow these thieves to force their personal ideology on citizens around the world".

People continuing to scour the list say they have found people including politicians and marriage counsellors on the list of registered users.