Three men behind in a phishing gang police believe stole over £4 million ($6.3 million) from credit cards and online bank accounts in the UK and Ireland have been sentenced to a total of 13.5 years in jail.

Arrested as part of the Metropolitan Police Central e-Crime Unit’s (PCeU) Operation Dynamaphone in August 2010, the trio, Ayodeji John Kareem, Vincent Alonge, and Babatunde Fafore, were accused of a fraud rampage that included the compromise of 900 online bank accounts and 10,000 credit cards.

The exact amount stolen is still not clear with the official figure recorded as at least £599,000 from compromised bank accounts and £570,000 of credit card fraud. Police believe the true credit card fraud figure was closer to £3.1 million with further unknown sums taken from bank accounts, which puts takes the scam over the £4 million mark, the largest of its type yet prosecuted in the UK.

The crime’s modus operandi involved the standard phishing design of luring victims to around 40 bogus bank web pages using emails, a criminal enterprise normally associated with offshore gangs beyond the reach of the UK police in Eastern Europe.

As simple as the operation was, much police time was taken up researching the network used by the men to stash their stolen proceeds. Some of it will likely never be recovered.

"These men profited enormously by taking advantage of the trust that many of us would place in an internet service that appeared genuine, but their enjoyment of their ill-gotten gains was short-lived,” said Crown Prosecution Service Central Fraud Group lawyer, David Levy.

Police haven’t described in detail the timeline of the men’s criminal activities but it is believed to be over a matter of months. As much as police have trumpeted the successful prosecution of the gang as a deterrent to others the fact remains that three men lacking any particular expertise were in a short period able to steal millions of pounds from banks accounts and credit cards using a relatively simple Internet scam.

Facing up to 21 years in prison, the three were given lower sentences after pleading guilty at earlier hearings.