Mobile viruses may be more prevalent than originally thought, according to security firm McAfee.

Speaking to vnunet.com at the Infosecurity show in London, Greg Day, European security analyst at McAfee, said that he was alerted to the issue during an informal conversation with a major European network operator at the show.

"I mentioned the lack of mobile viruses and he gave me a look and said we'll see a lot more of them soon," said Day. "I asked him for some data but got a 'not on your life'."

Mobile viruses have been around in proof-of-concept for some years now. They were first created by the Russian 29A hacking group and sent to antivirus researchers.

Since then there has been little overt activity, and most outbreaks have been limited because users have actively to accept the software onto their mobile phones.

However, the nightmare scenario for network operators is a mobile worm that damages phones or causes large numbers to dial premium rate numbers.