A BUSINESSMAN who pretended to be a secret agent has allegedly pocketed up to '300,000 from funds intended to pay investigators working on the disappearance of Madeleine McCann.

Kevin Halligen, a British security consultant, was paid to find Madeleine but allegedly failed to pass the money on to the private detectives who did the work on his behalf. A friend of Kate and Gerry McCann, Madeleine's parents, said they had become increasingly concerned about Halligen.

'He had this sense of cloak and dagger, acting as if he were a James Bond-style spy,' said the friend. 'He promised the earth but it came to nothing.'

Halligen's company Oakley International, which is based in Washington DC, was paid '500,000 after being hired by the Find Madeleine fund.

Sources close to Halligen say he offered to provide the McCanns with satellite images and lists of telephone traffic on the night Madeleine disappeared. The data were supposed to come from contacts in Washington but, one source claimed, 'all he came up with was a Google Earth image'.

The Madeleine fund was provided with further reports from teams of investigators who found it increasingly difficult to obtain their fees from Halligen. One of them, Henri Exton, a former national head of undercover operations for the British police, is owed more than '100,000 by Halligen for work he did on the Madeleine case.

Documents show that while Halligen's company was receiving the fund's cash, he was withdrawing large amounts of money for his personal use. He had been using company funds to finance first-class flights, expensive hotels and chauffeur-driven cars.

His contract with the fund was not renewed in October last year. Halligen left Washington for a holiday in Rome but never returned to Oakley's offices. He was last seen staying at the Royal Crescent hotel in Bath under an assumed name.

Halligen, 50, often pretended to have served in the intelligence services to impress business and social contacts, according to those who knew him well.

Two years ago he allegedly faked his own wedding to a lawyer in Washington, watched by former agents, a CIA station chief and an adviser to Barack Obama. Halligen told his bride that his spy masters would not allow his real name to be on wedding documents. He was, in fact, already married and the priest was an actor.

A wider financial investigation has found Halligen bought a '1m mansion with money allegedly defrauded from Trafigura, the company accused of dumping toxic waste in Africa. Last week the US Department of Justice issued an indictment seeking his arrest over the alleged Trafigura fraud.

Stephen Dorrell, the McCanns' MP, said: 'This man clearly saw a vulnerable family going through a terrible ordeal and the only thing he was focused on was that there were people offering money to help find Madeleine.'