A hoax email is being circulated claiming that entering a cash card Pin in reverse will alert police to a robbery taking place.

The message claims that new technology implemented by banks will allow cashpoint users to send a message to the authorities when they are being compelled to withdraw money.

People who are forced by thieves to withdraw money can enter their Pin in reverse when they get to the cash machine, the message says. The machine will give them the money as usual, but will also alert the police so that the muggers can be apprehended.

A number of Computeractive readers have contacted us asking if this is true, however, banking authorities have confirmed that the scheme is a hoax.

Sandra Quinn of payments trade association Apacs told Computeractive that the organisation was aware of the message, but pointed out that cash machines are not linked to the police. She said: "We're not sure where this came from, but it's one of those urban myths that circulate over the internet. What about people with numbers that are the same backwards and forwards, such as 6226?"

Cardwatch, the fraud awareness organisation, said in a statement: "The police will not be called, and you will not get any cash. If you enter your Pin in reverse the cash machine will register this as an incorrect entry and ask you to re-enter your Pin."

A similar scheme was proposed and patented by an American businessman in 1998, and it has been brought before the governments of three US states since then, but has been rejected each time. Apacs said that the scheme is not under consideration in the UK.

This hoax email follows on from one still circulating which Computeractive investigated last month. This is warning people of a premium rate scam, which is an urban myth, although an actual scam it was based on was stopped last year and the phone number is dead.

However these hoaxes often have a ring of truth and the last one we reported on even fooled the authorities and appeared as a warning on a number of some police, an MP's, local authority and trading standards websites.

If people are worried they are urged to think twice before being thrown into a panic and believing mass-mailed emails; check with organisations that could shed some light on the issue, such as premium rate watchdog Icstis or banking authorities.