The inner sanctum of the Bank of England was penetrated by a “powerful criminal network” linked to money laundering, terrorism, and contract killings, according to explosive intelligence that the police and MI5 tried to keep secret.

The details of the covert operation – which uncovered a suspected gangland plot so audacious detectives feared it could “destabilise” the British economy – are revealed for the first time in secret police files seen by BuzzFeed News and interviews with several well-placed sources.

The infiltration was discovered when detectives tapped the mobile phone of a Ferrari-driving businessman suspected of laundering money “on a vast scale” for organised crime gangs and reported hearing him receiving secrets from inside the Bank.

The major national security breach has been kept tightly under wraps by police chiefs and spies at MI5 for more than 16 years, shielding those implicated in the highly embarrassing scandal from public, parliamentary, and judicial scrutiny.

Although police warned senior bankers that a mole was passing inside information to a businessman connected to organised crime, the leaker was never identified, no one was sacked, and the businessman remains at large.

The Bank of England is now facing serious questions about how gangsters gleaned Britain’s most closely guarded financial secrets and how the public can be confident no such breach will occur again.

In 1998, as part of a major probe codenamed Operation Beregon, the detectives reported that they had eavesdropped on a high-rolling young stockmarket speculator receiving highly sensitive information about the bank’s monetary policy committee (MPC).

The committee meets in private each month to set Britain’s base rate of interest, which affects every aspect of the country’s economy, and the confidentiality of its deliberations is sacrosanct. Policymakers are made to sign a “declaration of secrecy” and are subject to “strict purdah rules” before decisions about interest rate changes are announced publicly. It is not suggested that the leak came from a member of the MPC.



But the businessman was believed to be exploiting a sexual relationship with the wife of a Bank of England insider to garner tip-offs about upcoming changes that could be used to gamble on the financial markets.

The threat to national security was deemed so severe that the investigation was swiftly taken over by spies at MI5, and the affair has remained a closely guarded secret for years.

A Bank of England source confirmed that in 1998 it was alerted to sensitive police intelligence that “two people were talking about inside access to the Bank’s information”.

The source said: “Leaking monetary policy stuff would have been, and still is, a hanging offence,” and an immediate internal inquiry was launched. But it failed to identify where the leak was coming from, so no action was taken and the case was closed.

However, some details of Operation Beregon are known to be contained in legal documents filed at the High Court last year by the lawyers of a former senior detective involved in the investigation who is now suing Scotland Yard.