A man who tried to sell Mohamed Al Fayed evidence that Diana, Princess of Wales, and his son Dodi were murdered has been arrested after demanding £10 million, it has been reported.
The Harrods owner arranged to meet the man in Vienna and drew him into a sophisticated sting operation involving American and Austrian investigators, according to reports.
Mr Al Fayed sent £1,500 to the man - named by Harrods as 68-year-old George Mearah to pay to get to the meeting and there was an initial exchange of documents, it was reported.
He also told the FBI who passed the information on to the CIA after the tycoon was first contacted a fortnight ago, according to the Kurier newspaper in Vienna.
The man, who was born in Vienna but emigrated to the United States, turned up for the meeting with Mr Fayed and his security chief John Macnamara in Vienna on Friday.
He was seized by Vienna security police, who had been listening in on the discussions, after he detailed his demands, according to the Austrian newspaper.
The American made death threats against Mr Al Fayed and Mr Macnamara, Harrods director of security, after the arrest, according to Harrods.
He appeared before a magistrate on Friday and was remanded in custody, according to the Kurier newspaper.
A statement from Harrods said: "The case follows a two-week enquiry by Mr Macnamara in Washington and Vienna into allegations that British Intelligence sought the help of the CIA in a plot to assassinate Diana, Princess of Wales and Dodi Fayed.
"Working with the full cooperation of law enforcement authorities in the United States and Austria, Mr Macnamara was also investigating the alleged existence of documentary evidence of such a plot.
"There are no further details at present as enquiries are continuing in the United States and further charges are anticipated."
Mr Al Fayed has previously claimed that Diana and Dodi were assassinated and in February said he was "99.9% certain" that the crash in a Paris underpass on August 31 last year was not an accident.
He met the examining magistrate, Herve Stephan, for the first time last month and said he had "total trust" in the investigation.
After the meeting, Mr Al Fayed's lawyer Georges Kiejman was asked if Mr Al Fayed still thought it was an assassination.
He said: "No theory is ignored. But, at the moment, we remain within the framework of a ride that was too fast, provoked by a chase by journalists and a tragic accident for which the responsibilities will have to be established by the judge."
Mearah contacted Mr Al Fayed two weeks ago and said he could back up the murder conspiracy theory, according to the Kurier.
The paper said reports about the money the man asked for varied but went up to nearly £10 million.
The Kurier said he showed Mr Al Fayed two documents which had appeared genuine and proved his theory that the Establishment was trying to block Dodi from marrying Diana because he would become the step-father of a future king.
Mearah allegedly warned Mr Al Fayed not to inform the police but Mr Al Fayed went ahead anyway, according to the paper.
After prolonged negotiations, the meeting was held in Vienna where the man was arrested. A police spokesman told the newspaper: "It seems that there was no truth in his claims whatsoever."
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