Internet security specialist David Lacey of the Royal Mail warned that cyber-crime is increasing in sophistication but is not yet fully mature

In the next two years, he said, the potential rewards for e-criminals will grow to new levels, together with their ability to cause damage.

We need new, intelligent e-security systems, he stressed.

"Do not think that traditional ways of doing security will work. They won't. They'll break down," he said. "Existing solutions will increasingly fail to cope with the complexity of emerging networks."