In the last two weeks, almost 60 people have been arrested for trading banking and credit-card details on a criminal website, in an FBI-led sting.
The arrests of people involved in the DarkMarket forum have followed a two-year, international police operation in the UK, US, Germany and Turkey. The forum, described by the Serious Organised Crime Agency (Soca) as "one of the most pernicious online criminal forums in the world", enabled participants to buy and sell personal data, and trade in equipment used in financial crimes.
Sharon Lemon, deputy director of e-crime for Soca, which aided the FBI operation, said that some suspects remained at large in the UK and overseas.
"The people involved in this kind of activity are not technical experts. They are thieves with keyboards, and they have a certain arrogance; they think they are untouchable," said Lemon. "We are making the UK a more hostile environment for serious organised crime."
Soca's work with City of London Police and Greater Manchester Police resulted in 11 UK arrests this week. The arrests took place in London, Manchester and Leicester. Previous arrests of DarkMarket traders over the course of the two-year operation have been facilitated by Humberside Police and South Yorkshire Police, said Soca in a statement.
DarkMarket, which was infiltrated by an FBI agent using the pseudonym 'Master Splyntr', featured breaking-news style updates on the latest compromised personal information while it was still active and able to be abused. The site was closely guarded and inaccessible to most web users. It was operated on an invitation-only basis, said Soca.
Richard Archdeacon, Symantec's director of global security, said that it was difficult to "pin down" participants of such sites.
"They move very quickly and operate in different geographical regions," said Archdeacon. "Soca and the FBI's achievement is really quite something."
Credit-card details on fraud forums are priced according to volume, said Archdeacon, with US data typically retailing at 40 to 50 cents (23 to 29 pence) for name, credit-card and CVC numbers. European card information is more expensive than US data, said Archdeacon, probably due to the relative volume of compromised US card details.