Security experts have warned internet users to beware of new worms exploiting this year's Valentine's Day.

Panda Security has identified the worms as Nuwar.OL and Valentin.E.

"Year after year we see several malware strains that use Valentine's Day as bait to attract users," said Luis Corrons, technical director of Panda Labs.

"This indicates that cyber-crooks are still reaping the benefits of this technique and many people still fall into the trap."

Nuwar.OL reaches computers by email with subjects like 'I Love You Soo Much,' 'Inside My Heart' or 'You In My Dreams.'

The body of the email includes a link to a site that downloads the malicious code. The page is very simple and looks like a romantic greeting card with a large pink heart.

Once it has infected a computer, the worm sends out a large number of emails to the user's contacts in order to spread. This also creates a heavy load on networks and slows down the computer.

Valentin.E is very similar, using subjects like 'Searching for True Love' or 'True Love' and containing an attached file called 'friends4u'.

A copy of the worm is downloaded and installed on the computer as a file with the .scr extension if the targeted user opens the file.

Valentin.E shows a new desktop background to trick the user, while making several copies of itself. Finally, the worm sends out emails from the infected computer to spread and infect more users.

"Both cases are clear examples of social engineering techniques to spread malware," said Corrons.

"They use attractive subjects, such as Valentine's Day greeting cards, romantic desktop themes etc, to entice users to run attachments or click links that ultimately download malware."