The fraudsters used stolen credit card numbers to create false identities to purchase expensive electronic equipment and other goods, which they then resold on eBay. Police believe the global campaign could have spanned a decade.
The authorities closed in on the gang after Spanish police caught one of the lieutenants. Documents seized in the arrest identified Dolgov and agents issued an international arrest warrant for him.
Officers from the Serious Organised Crime Agency (SOCA) then discovered the criminal's London premises after a burglary was reported next door. Agents raided the property and found Kostap plus incriminating material including documents relating to false identities and CDs containing the names of thousands of American births and deaths.
Despite being handcuffed, Kostap managed to jump up and flick an electrical switch that wiped a computer database that could have held more records of the criminal group's activities, said police.
"It is quite clear that the total amount of money defrauded will probably never be known," said prosecutor David Hewitt. "These conspirators were prolific identity creators running an organised business."
Hewitt said £750,000 was known to have been defrauded and £56,000 in stock was recovered from the thieves' premises.
The mastermind, known as Kaljusaar, is still on the run, according to officers.