The Lovebug virus struck millions of PCs worldwide

Police, companies and experts looked at ways of tackling the growing problem of internet crime at a conference.

Experts believe virus and trojan attacks, spam email and hacking cost Welsh firms millions of pounds a year.

Around 200 delegates discussed an action plan in Llangollen on Wednesday.

It was drawn up at a first conference, held in Cardiff a year ago.

Joining representatives from all four Welsh police forces were the national hi-tech crime unit, Microsoft and the Welsh Development Agency.

Businesses are being urged to review their security procedures.

The importance of effective 'firewalls', password policy and virus checking were also highlighted.

Companies are being advised to make sure they keep regular back-ups of data critical for their business.

'Zombie' infection

One company taking part in the conference was cheese-maker South Caernarfon Creameries which has already faced disruption from malicious 'worm' code.

The dairy's computer system became infected by a virus which turned a server into a 'zombie' that sent out thousands of spam emails.

The firm was left off-line for two days after its internet provider shut the system down.

BOOSTING CYBER SECURITY Use anti-spyware and anti-virus programs Make sure updates to your operating system are installed Use an Internet firewall and make sure it is switched on Use complex passwords and change them often Protect the physical security of hardware Keep secure back-ups of important data

Senior police officers say the threat from such attacks is very real.

"High-tech crime, as with all reports of crime, is taken extremely seriously," said Detective Superintendent Chris Corcoran of North Wales Police.

"However, when it comes to crime prevention, everyone can take active steps and measures to protect themselves from on-line criminals".

He added: "Learning to close doors and windows to prevent criminals entering is as pertinent to electronic security as it is to physical security".