If you have ever claimed a tempting-sounding prize on a premium-rate phone number or postal competition, you might have inadvertently added your name to a list set up to identify people susceptible to telemarketing.

These "sucker lists" are often sold to conmen and the victims inundated by telephone, text and e-mail with fraudulent offers including fake lotteries, bogus investment plans and work from home schemes.

In response to the problem, the Office of Fair Trading (OFT) has launched a 30-day campaign to help consumers identify fraudulent offers.

In partnership with the Department of Trade and Industry (DTI), the OFT has distributed more than half a million leaflets and posters containing advice on how to recognise and guard against the scams.

"Last week we named the top ten scams targeted at UK consumers," Penny Boys, the executive director of the OFT, said. "But next year, there will be new frauds and swindles to part people from their money.

"Our campaign aims to equip consumers with the skills and knowledge to recognise scams, whatever their form, and so prevent themselves and others from falling victim to persuasive and manipulative approaches."

The leaflets explain that most scams have common elements designed to hook victims.

These include offering tempting and easy opportunities to make money; asking for money up-front to claim a prize to cover administration fees or taxes; asking for bank details or to ring a premium rate phone number.

They also warn consumers not to be fooled by a well-spoken accent or slick, professional-looking leaflets and to be wary of unsolicited callers that are overly persistence or attempt to rush you into making a decision.

Gerry Sutcliffe MP, the minister for consumer affairs, said the DTI was targeting telephone conmen.

"I have a warning for those running or thinking of running scams - the DTI is committed to working closely with enforcement agencies to put a stop to this activity, and bring the full force of law to bear."

But a problem for the authorities is that many of the scams are conducted from abroad.

The OFT has powers to shut fraudulent operations run from within the EU but it can be much harder to trace and close schemes operated from outside Europe.

Q&A: how to avoid becoming a sucker

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