An online conduit accused of spreading vast amounts of malicious and criminal content has closed down its base in St Petersburg sparking fears that the operation will surface elsewhere.

Security firm Trend Micro said that Russian Business Network (RBN) dropped off the internet last Tuesday, and has predicted its emergence in a newly reinvigorated form somewhere in Asia.

Run by a shadowy figure known only as 'Flyman', RBN has been associated with a number of high-profile online crimes committed in the UK.

Security firms have linked RBN to child pornography, corporate blackmail, spam attacks and online identity theft, according to a report in Times Online.

"The UK has been a focus for this group and its criminal clients, and things are set to get worse," said David Perry, an analyst for Trend Micro.

The US Treasury estimated recently that cyber-crime is now worth $100bn a year, more than the illegal drugs trade.