The UK Threat Assessment of Serious Organised Crime report says a criminal market has evolved for the "compromise, trade and exploitation of personal data".

Soca says international multi-skilled virtual gangs of up to 30 members - each with specialist roles, from spamming to data trading - are meeting and keeping in touch in Web forums and Internet relay chat channels.

"Each group will typically have an inner circle of more technically advanced and/or experienced members who control access to the attack tools and are responsible for dividing up the work," says the report.

The gangs steal personal information through phishing and installing key logging malware on victims' computers using spam e-mail. Large databases containing the personal information of customers and employees are also being hacked, warns Soca.

The gangs then use the stolen data to commit fraud themselves or utilise the Internet as an anonymous marketplace, selling the information directly to other crooks.

In counterfeit payment card fraud, different groups of criminals are involved in sourcing details and in manufacturing and using the cards, says Soca. Niche service providers exist who procure, produce and supply false documentation, make ATM withdrawals and open fraudulent bank accounts.

The Soca report says these cyber criminals continually adapting their tactics as new defences are implemented by software and anti-virus vendors.

"As Web-based technologies become increasingly diverse e-criminals will use these services to access and exploit victims and conceal their activities," says the report.

A federal grand jury in Los Angeles has charged 33 people - 22 Romanians, five Vietnamese, three Americans, one Cambodian, one Pakistani and one Mexican - in a 65-count indictment, according to the US Department of Justice.