SHOPPERS hunting a Christmas bargain are being urged to be on their guard against a telephone scam that could leave them with nothing to show for their call but a big phone bill.

The trading standards team in North Yorkshire is urging people not to call premium rate numbers as they search for cheap goods.

It follows a complaint from a woman who responded to a private advert for the popular PlayStation 2 computer game system which had been described as an unwanted gift.

When the woman rang the number given she was given a number of excuses and told to stay on the line.

However, after becoming suspicious she hung up, called BT - and was told she would be charged £1.50 a minute for the earlier call.

Trading standards officers from North Yorkshire, armed with a search warrant, raided premises in Lincolnshire and a man has since been arrested and is under investigation for a number of alleged offences.

The head of the county trading standards team, Stuart Pudney, said yesterday: "People should be aware of calling premium rate numbers because they always start with 090.

"They are considerably more expensive than normal numbers because of the charging system.

"The company or individual which set up the number collects a percentage of the charge made from premium rate numbers.

"It is possible that anyone setting up a premium rate number will make a substantial amount of money from incoming calls - particularly if people are left hanging on.

"In this particular case, and we don't believe it was an isolated example, the caller was left hanging on the line for several minutes before realising the situation."

The Independent Committee for the Supervision of Standards of Telephone Information Services requires that appropriate pricing information should be provided in advance of consumers ringing such a number.

The information should be in the form of a price-per-minute or the total cost to the consumer including VAT.