With his links to the Royal Family, his international lifestyle and his impressive physique, Michael Garveigh was the perfect British secret agent.

When the wealthy businessman was introduced to American police as an MI5 officer who required help in an antiterrorism operation, there was no reason to doubt him. But he has been accused of posing as an intelligence officer to trick the police into helping to carry out robberies by removing cash from houses supposedly used by terrorists.

Mr Garveigh, 45, a former classmate of the Earl of Wessex, has been arrested on a charge of impersonating a foreign official, but he insists he is the innocent victim of a sophisticated fraud.

The FBI says that the British businessman and an American friend pretended to be part of a special counter-terrorism task force during meetings with two city police forces on the outskirts of Atlanta, Georgia. Mr Garveigh, who has an American wife, has lived in Georgia for the past four years.

The two men are alleged to have requested help from senior officers to recover terrorists’ money during raids at several locations scheduled for the week starting today, Independence Day.

The friend, Louis Aprile, claimed to be a regional deputy director of the National Security Agency during at least five meetings with police officers in the cities of Alpharetta and Marietta. According to an affidavit by FBI Special Agent Matthew Carman, he was accompanied to at least three meetings by Mr Garveigh, who was portrayed as a British intelligence officer.

Mr Aprile, 49, told the police they were investigating a terrorist group with cells in Detroit, Michigan and Britain that planned to buy milk trucks in Florida and pack them with explosives, it is alleged. During one meeting Mr Garveigh left the room to receive phone calls. He returned from one saying that British officials, including himself, were being scrambled to deal with North Korea’s nuclear test.

Although the police officers were instructed not to contact anyone about the top-secret operation, someone consulted the FBI, which discovered that neither man was a secret agent. A final meeting between the pair and the police was recorded secretly by the FBI. During the meeting Mr Aprile revealed the locations of three addresses to be raided.

Katherine Hoffer, an assistant US attorney, said: “I’ve seen impersonating cases but this one is pretty elaborate. They’ve offered some explanations but nothing that really had any merit.”

An FBI agent involved in the investigation said: “I’ve never seen two such clever guys do something so stupid. It was a very bold attempt to scam a police department to help them carry out a crime.” He claimed that the men had told officers they wanted to recover large sums of money from the locations of the raids, while the police would have the glory of arresting dangerous terrorists.

The FBI has refused to reveal the intended locations of the alleged raids. However, Brian Will, who lives near the Garveigh family, believes he was one of the targets. He said that he had sued Mr Garveigh for $100,000 after he failed to complete a $150,000 project to install a security system at his home.

After their arrest Mr Aprile was described as a software contractor and Mr Garveigh as a self-employed commodities broker. Each has been released on bail of $20,000. They have said they intend to deny any wrongdoing.

Mr Garveigh is from a wealthy Anglo-Portuguese family that has made a fortune from development of the Algarve. He was educated in Britain and was in the same year as Prince Edward at Gordonstoun, the Scottish public school, which was also attended by the Prince of Wales and the Duke of York. After attending Loughborough University he returned to Portugal to set up a landscaping business.

Four years ago Mr Garveigh moved to Georgia with his American wife, Victoria, and their son and set up a business supplying internet wireless services. The family lives in a gated community in Roswell, a smart suburb of Atlanta.

Friends say they are amazed at the allegations surrounding Mr Garveigh. Anthony Carlyle, a former director of Mr Gaveigh’s British subsidiary, said: “He is a great guy and totally honest. He would never get involved in crime. It is totally laughable. I suppose he was a bit like James Bond but he is the most down-to-earth person.”

Mawuli Mel Davis, Mr Garveigh’s lawyer, said: “My client is as much a victim in this as anyone else. He has been misled by someone he trusted and he will be cleared of all criminal charges. The person he trusted told law enforcement officers that he was a British intelligence officer and Mr Garveigh did not correct that impression. But he thought he was legitimately helping an investigation.”

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