IT security experts today advised credulous PC users not to be taken in by a newly discovered worm which displays a message purporting to come from an extraterrestrial.

The Sundor-A worm displays a picture of an alien with the following message: 'I'm the alien. Have a happy week. I liked your computer.'

According to security firm Sophos, the worm deletes programs and documents from the hard drives of infected computers.

It can also hide desktop icons and disable security software, potentially leaving the computer open to infection by other worms, viruses and spyware.

"The good news is that you're more likely to be abducted by an alien than infected by this virus," said Graham Cluley, senior technology consultant at Sophos.

"Sundor-A has so far been remarkably unsuccessful at spreading its message to the inhabitants of planet Earth.