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World number one John Higgins has been suspended from all future tournaments after reportedly agreeing to take a £261,000 bribe to lose frames.
World Snooker chairman Barry Hearn said he had to take "drastic action" following the News of the World report.
The paper says it has video of Higgins and manager Pat Mooney making a deal.
There is no suggestion Higgins has ever thrown a frame or fixed a match and he said: "I have never been involved in any form of snooker match-fixing."
The newspaper's video reportedly shows Mr Higgins and Mr Mooney meeting with an undercover reporter in Kiev, Ukraine, and agreeing to alter the outcome of frames in return for money.
In response to the allegations, Mr Higgins released a statement protesting his innocence, stating: "My conscience is 100% clear.
"In my 18 years playing professional snooker I have never deliberately missed a shot, never mind intentionally lost a frame or a match."
Later on Sunday Mr Higgins admitted he was facing the "the biggest match of my life".
"It's not the World Championship that's at stake, it's something even more important, my reputation," he said.
Mr Mooney, who has since resigned from the board of the World Professional Billiards and Snooker Association (WPBS), is reported to have told the News of the World: "You have no idea what the circumstances were in Kiev, that's why I have no comment.
"But we were genuinely in fear for our safety."
And that is a claim supported by Mr Higgins.
"In all honesty I became very worried at the way the conversation developed in Kiev," he added.
"When it was suggested that I throw frames in return for large sums of money, I was really spooked. I just wanted to get out of the hotel and onto the plane home.
BBC team on Higgins allegations
"I didn't know if this was the Russian Mafia or who we were dealing with. At that stage I felt the best course of action was just to play along with these guys and get out of Russia."
However the News of the World said it was "surprised" at Mr Mooney's suggestion of intimidation and that the paper's investigations editor had had three meetings with Higgins's manager in Edinburgh.
"We assume Mr Mooney did not feel intimidated during these meetings where he openly discussed John Higgins and match fixing," said the News of the World in a statement.
"In a number of conversations he [Mr Mooney] explained how a snooker game could be fixed, the amount of money required to facilitate it and repeatedly assured us that Mr Higgins would be 'relaxed' with the arrangement.
"At no time whilst in Kiev did Mr Mooney or Mr Higgins show any signs of being under duress or in any way unhappy at being in our company," added the News of the World, which promised to publish further revelations next weekend.
Promoter Mr Hearn said the disciplinary process, led by WPBSA board member David Douglas, the former Metropolitan Police detective chief superintendent, would take "days and weeks" rather than "months and months", with the new season set to start in July.
"I take the view that this is a very serious matter," said Mr Hearn. "It is a matter that affects the integrity of the sport potentially, therefore we have a responsibility not just to our snooker fans (but to) our broadcast partners, our sponsors, anyone who's associated with the sport."
Everybody is in shock. Everyone's walking around in bits
Steve Davis
"While we are not saying John Higgins is guilty of anything, we feel the revelations are such that he has a case to answer," added Mr Hearn. "While that process is under way, he will be suspended.
"The message is clear to anyone involved in snooker, any doubts about the integrity of the game will not be tolerated by this administration, and they will be dealt with in a very harsh but fair manner."
Mr Hearn also told the BBC that anyone found guilty of match fixing would receive "a very, very, very lengthy ban".
Six-time world champion Steve Davis was stunned by the news on what he called "a dark day for snooker".
"Everybody is in shock. Everyone's walking around in bits," said Mr Davis, who unexpectedly knocked Mr Higgins out of the World Championships in the second round.
Asked whether Mr Hearn might be tempted to walk away from snooker, Mr Davis replied: "There is the possibility that with Barry Hearn in the process of taking the game over, he may be able to cut the cancer out of it from day one."
Hearn plots snooker revolution
Earlier Mr Hearn said he was "absolutely mortified" and the story had come as a "huge shock".
"It was as if someone kicked me in the stomach. We are working very hard on the reinvigoration of the game and this is a huge backward step," he said.
"Those responsible, if proved, will be dealt with in a very harsh and brutal way. People have a right to see pure sport - that's what I want snooker to be."
Mr Hearn has spoken to Mr Mooney, who also manages World Championship finalist Graeme Dott, and told the BBC: "Mr Mooney has got his own reasons - I won't say say excuses - for why he believes he was set up for this.
"But I don't want to go into that, that is for Mr Mooney. What I want to do is make sure the integrity of the sport is protected at any cost and at all times."
The newspaper alleges that Mr Higgins inquired at the meeting about the best ways to conceal the 300,000 euros ($398,000) to be received for losing frames in four separate matches later this year.
In a published transcript, Mr Higgins, 34, from Wishaw, North Lanarkshire, says it would be easy to affect the outcome of a frame.
I want to meet with the players on Wednesday anyway to discuss it. And this is now top of the agenda
Barry Hearn
Many bookmakers now offer the option of betting on individual frames.
After transforming the popularity of darts as chairman of the Professional Darts Corporation, Mr Hearn became chairman of the WPBSA in December.
He recently proposed an overhaul of the sport including rule changes and boxing-style introductions for the players and admitted these allegations could damage the sport long term.
"I've known John Higgins for a long, long time," said Mr Hearn, who added that the newspaper allegations had forced him to consider his plans for the sport.
"I want to meet with the players on Wednesday anyway to discuss it. And this is now top of the agenda."
The World Snooker Championship final between Dott and Neil Robertson in Sheffield takes place on Sunday and Monday.
Mr Higgins, who was made an MBE in 2008 and is married with three children, is the current world champion, provisional world number one and has won a total of 21 ranking titles.
And Higgins added: "Those who know me are aware of my love for snooker and that I would never do anything to damage the integrity of the sport I love."
Video of what happened here: