Troels Oerting, the head of the European Cybercrime Centre (EC3), has blamed the "darknet" for making it difficult to catch cyber-criminals in his keynote speech to Infosecurity Europe in London.
Furthermore, he added, the revelations of former US National Security Agency (NSA) contractor Edward Snowden that security agencies around the world are engaged in widespread surveillance has also made the job more difficult, he added. "The Snowden revelations seemed to, one way or another, have made it more difficult law enforcement to clamp down," said Oerting.
And the "darknet" - or more properly the "deep web", which can be used via tools that encrypt and anonymise people's browsing - cannot easily be penetrated by law enforcement, he said.
"The problem is that criminal groups are using the same tools... You can't see the attack, don't know the motive... you need to do some homework."
And although TOR, the software typically used to browse the deep web, was originally developed with the help of the US Naval Research Laboratory, penetrating the activity over the network is a challenge. "Not even NSA can infiltrate the darknet, cyber-criminals are utilising Bitcoin and the darknet, it makes it even more difficult for us to follow the money," said Oerting.
The challenge is made all the greater by the numbers of people around the world going online, with numbers of users expected to increase from 2.7 billion to more than four billion as mobile technology takes the internet to more and more remote places.
Furthermore, much cybercrime is cross-border, with poor levels of co-operation with countries like Russia where many of the cyber-criminals reside.
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