A secret FBI bugging operation at the London 2012 Olympics could have uncovered key evidence which led to the arrest of top Fifa officials in Switzerland earlier today.
The six arrests followed an international investigation into bribes and 'kick backs' by America's federal law enforcement agency and tax authority, the IRS.
An American newspaper, the New York Daily News, has revealed details of the undercover operation said to involve former Fifa executive Chuck Blazer.
The ex-chief executive of CONCACAF, football's governing body in America and the Caribbean, is said to have secretly recorded conversations at London Olympic venues.
The FBI is believed to have fitted a tiny microphone into his hotel key fob which he used to spy on colleagues.
The Daily News claims he would 'toss his bugged key fob on a table to secretly record fellow international soccer executives.'
The wiretap is said to have been carried out with permission from Scotland Yard.