Dark web 'will evolve', warns UK cyber crime chief Andy Archibald
11 October 2013 Last updated at 14:00 BST
The "dark web" services used by criminals will continue to evolve in an attempt to evade authorities, it has been warned.
Last week, clandestine online drugs market place the Silk Road was shut down after a lengthy investigation.
Andy Archibald, the interim head of the UK's National Cyber Crime Unit (NCCU), said his officers worked with the FBI to identify individuals who were buying and selling drugs through the anonymising networks.
But he added that different tools and methods would need to be adopted if his team is to keep up with the constantly-evolving threat.