A BBC investigation has raised concerns that a cycling event may have bought its way into the Olympic Games.
Documents given to the BBC suggest that $3m (£1.5m) was paid by organisers of a Japanese cycling event to the UCI - the world cycling body.
The payments were allegedly made in the 1990s. The event, called the keirin, was supported for inclusion into the Games by the UCI, and admitted in 1996.
The UCI and its president at the time, Hein Verbruggen, deny any wrongdoing.
The keirin is a rapid and exciting track cycling event where riders are initially paced around a track by a motorcycle before sprinting for the line.
One of Great Britain's best Beijing medal hopes, Chris Hoy, is the current world champion in the discipline.
The keirin is big business in its country of origin, Japan, commanding tens of millions of dollars in gambling revenue every year.
But despite its financial clout, the one thing the event has always lacked is an international profile.
'We should really stop it'
Back in the 1980s the Japanese successfully lobbied to put their race into the world track championships organised by the Union Cycliste Internationale (UCI).
The keirin event was admitted into the Olympics in 1996
It was a move that, according to Mr Koramasu of the Keirin Association, was initially greeted with some scepticism by the incoming UCI President Hein Verbruggen.
"In 1992, the world championship was considering dropping the keirin and it was a shocking thing for us.
"It started when Mr Verbruggen of UCI proposed dropping keirin from the world championships and we thought we should really stop it."
But four years later the tables had turned completely.
Not only was the keirin a fixture in the world championship, it was - by 1996 - preparing to receive the ultimate prize for any sport, a place in its own right on the roster of the Olympic Games.
The keirin was formally accepted by the International Olympic Committee in December of that year and entered competition in Sydney in 2000.
Everybody knew the Japanese were supporting the world cup series and were supporting everything and I think everybody realised that they weren't doing it for nothing
So how did such a remarkable turnaround occur?
For years there have been rumours in cycling that the Japanese gave money to the UCI in return for its promotion of keirin as an Olympic event.
According to one member of the UCI at the time, the Japanese donated a "big envelope" in return for access.
Denmark's Henrik Elmgreen was also a member cycling's governing body at the time.
"We must admit that when they came it was because the Japanese were very influential in the UCI and they offered a lot of money in order to promote this discipline.
"You can to a certain extent say they bought their way in but on the other hand it is a spectacular discipline.
"Everybody knew the Japanese were supporting the world cup series and were supporting everything and I think everybody realised that they weren't doing it for nothing.
"They wanted something in return and everybody knew what they got in return."
'No transfer of money'
Mr Elmgreen says that everyone knew, but we have found no formal declaration of such a deal's existence.
... critics say that the system by which events go in and go out of the Olympics is seriously flawed, with little or no oversight
In fact, when we asked Mr Karamasu of Japan's Keirin Association, he categorically denied the deal had ever taken place.
"No transfer of money took place.
"What we did is that we supported establishing the cycling training centres in Japan and also we paid the set amount that all the National Federations pay for membership… sort of a membership fee - I have to say I do not know about it at all.
"I have been in this position up until 1998 however I've never heard of any direct payment of money or cash"
But documents given to the BBC suggest a different story.
They reveal a series of substantial payments to the UCI, which began just two months after the keirin was accepted into the Olympics in December 1996.
Written on UCI letterhead one of the contracts states that the Japanese agree to support UCI projects in "material terms", in consideration of "the excellent relationship the UCI has with representatives of the Olympic movement".
The payments total some $3m - that is about a fifth of the UCI's annual budget - paid as reimbursements for things like the routine travel expenses of top UCI officials including Mr Verbruggen, the man who is now in charge of the organising committee for the Beijing Olympic Games.
Hein Verbruggen denies any wrongdoing
In one six-month period in 1999, for instance, the Keirin Association paid for no fewer than five separate return flights on UCI business taken by Mr Verbruggen to the Netherlands, his home country.
A source who was within the UCI at the time has told the BBC that the payments were explicitly a payback for getting the keirin into the Games.
We took these revelations to Mr Verbruggen himself who denied that anything improper had taken place.
"It's been done in total transparency", he said. "This was done for the development of track cycling around the world."
However he did not directly explain how come routine air fares and other UCI expenses were being covered by the Japanese.
We contacted the UCI to try and get some clarity on these allegations. They ignored our request.
'Matter of trust'
We then tried to get some clarity from the International Olympic Committee.
Britain's Sir Craig Reedie is a member of the IOC's ethics commission which oversees such allegations. However he said it was not directly a matter for his organisation.
"The International Federations have their own set of rules. We would trust our International Federations to get this correct. It is a matter of trust."
The organisation's critics say that the system by which events go in and go out of the Olympics is seriously flawed, with little or no oversight.
Their argument is that if you are careful enough and clever enough and you really want the golden Olympic ticket for your sport, there is every reason to believe that you can get your event onto the podium.
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