Security experts today warned of new image spam that tries to tempt gullible recipients into opening emails by offering to find them prostitutes.

The emails contain the subject line 'How about finding a girl in your town who is ready to help you take the pressure off?'.

The messages include an image containing a link, which must be typed in manually by the recipient, as well as several sentences of seemingly random text.

If recipients type the link into their web browser, it will take them to an explicit website offering a search tool for finding prostitutes based in their area.

"Image spam is often used for promoting things designed to improve your sex life," said Graham Cluley, senior technology consultant at Sophos.

"This latest campaign goes a step further than the usual emails offering drugs and medication, all of which presuppose that the recipient has a way of testing them.

"While there is nothing malicious about the emails or the website, the majority of users will find this type of content inappropriate and offensive, and must look to anti-spam solutions if they want such filth eradicated from their inboxes."

Image spam, which uses a graphic embedded in an email rather than regular text, has grown in popularity among spammers attempting to communicate marketing messages to internet users.

Image spam is often used for promoting stock pump-and-dump scams or drugs to help with weight loss or sexual performance.