The e-mails are a variation on a postal scam

Internet users are being urged to ignore e-mails asking for help in transferring large sums of money out of Nigeria, South Africa and Sierra Leone.

The e-mails are a variation on a scam which has been operating for years through the international postal service.

Fraudsters posing as high ranking officials in an African government ask recipients to give details of their bank or building society accounts to facilitate the transfer of huge sums of money out of countries like Nigeria, South Africa or Sierra Leone.

The e-mails are marked 'secret' or 'confidential' and promise up to a quarter of the funds in return for using the account.

But the Police Service of Northern Ireland has warned recipients not to reply to any suspicious material they receive by post fax or e-mail.

'Scam'

The head of the PSNI's Fraud Unit, Detective Chief Inspector Larry Cheshire, said there had been cases where companies sending polite letters of refusal had their letterheads used by the gangs.

"Any contact will be followed up with a request to meet to discuss the deal," he said.

"This will usually take place on mainland Europe and will lead to a requirement to provide an upfront payment (an advance fee) to secure the release of the money.

"The whole thing is a scam and is purely designed to part victims from their cash.

"There have been instances of Northern Ireland residents losing out to these conmen, so beware.

"If it sounds to good to be true, then it is."