Near the beginning of an Italian soccer match in Tuscany on May 23, 2010, a man from Singapore named Tan Seet Eng spoke on the phone with a Croatian associate. He told the associate he needed at least three goals to be scored in the match between Grosseto and Reggina.
"No problem," the associate said, explaining he had someone working for him at the match. With that simple exchange, Italian prosecutors say, the fix was in.
The phone conversation illustrated the power of Mr. Tan, a shadowy figure living in Singapore who was called "the boss" and "the capo" by his accomplices and is suspected of fixing dozens of games as easily as he did that 2010 match in Tuscany.
The game is among about 100 matches played from 2008 to 2011 in Italy's top three soccer leagues that are under investigation — and among 680 matches worldwide considered suspicious by European law enforcement, which reported the results of a 19-month match-fixing investigation last week. European investigators believe Mr. Tan was a common link in many of the matches.
Little is known about Mr. Tan, who is also called Dan Tan. Italian authorities said they were not even sure what he looks like. Their only photo of Mr. Tan is several years old.
"I can't tell you Tan's personality or how he speaks," said Roberto Di Martino, one of the lead prosecutors in Italy's match-fixing investigation. "Tan is a question mark."
Mr. Di Martino added: "I have no idea where Tan takes all the money from, what he does in life. From the picture that we have, he looks like he was 15."
Mr. Tan, who is reportedly in his 40s, could not be reached for comment. A security guard at his last known address, Rivervale Crest, a condominium in a middle-class neighborhood in northeast Singapore, said he moved out several months ago.
Italian authorities issued an arrest warrant for Mr. Tan in November 2011 and forwarded it to Interpol, the international police agency. So far, its search for him has been unavailing.
But the findings of the Italian inquiry — 50,000 pages and transcripts of about 200,000 phone conversations — offer a sketchy portrait of Mr. Tan and how his match-fixing syndicate, as described by the police, flourished for years.
A Simple Business
The syndicate's methods were not particularly complex, investigators said. Mr. Tan and his associates used Milan as a gateway for their endeavors in Italy. They often stayed at hotels near Milan's Malpensa Airport, the Grand Hotel Malpensa and the Crowne Plaza in Somma Lombardo. They even booked the same room on return visits. At the Crowne Plaza, Mr. Tan "has always paid in cash," the report said.
Among Mr. Tan's collaborators were those referred to as the Eastern men — from Eastern Europe. Their boss was Almir Gegic, a former Serbian player. The Eastern men made direct contact with players in hotels where they stayed during training camps. That was where the bribes were made, investigators said.
There was frequent communication between those who dealt with players and the Singaporeans who transported the money for bribes. The most important call was between Mr. Tan and Vinko Saka, a former coach from Croatia who would tell Mr. Tan when a bribe was arranged.
(Read More: Silence in Match-Fixing Probe Puts Singapore at Risk)
"The picture is just not that of simple dishonesty of players and coaches at the local level, but rather one of an operative international network, eased by the 'globalization' of betting on the Internet, capable of convincing disloyal players ready to fix matches and earn easy money," the inquiring judge, Guido Salvini, wrote in a statement.
"This cartel is probably not the only international cartel that works in this criminal field, but it's the first one that has come to light."
The main charge against Mr. Tan in Italy is criminal association targeted to international sports fraud. There are more than 150 people under investigation who face a prison sentence of up to 10 years. Mr. Tan could receive a 15-year sentence if he is found to be the leader of the ring.
"He will certainly be tried in Italy," Mr. Di Martino said. "Most of the people under investigation here will likely plea bargain, but there will most surely be a trial against all those who deny wrongdoing or have not been arrested or found yet."
More From The New York Times:
Network of Singaporeans
In a region that struggles with corruption and poverty, Singapore is envied as a prosperous and neatly manicured country with very low crime rates and a reputation for efficiency and the rule of law. But European police forces say that an underground network of Singaporeans sought to fix the outcome of soccer matches on at least three continents — and reap millions of dollars in profits from bets they placed on the outcomes.
"The investigations around the world out of Africa, Central America and Europe are pointing primarily to match-fixers out of Singapore," said Chris Eaton, the former head of security at FIFA, the governing body of international soccer, who helped lead the investigation before leaving for a job at a private sports security company.
"The evidence that I see is incontrovertible — the testimony of players, testimony of people involved in the syndicate and interviews of people who still work in these syndicates," Mr. Eaton said.
Investigations in Germany, Finland, Croatia and Hungary have also led to Singaporean syndicates.
Mr. Di Martino said he had received little information from the Singaporean authorities about Mr. Tan.
In December 2011, the Italian police wanted to go to Singapore and arrest Mr. Tan, but they struggled to gain entry.
"As far as I know, there has not been much cooperation in Singapore," Mr. Di Martino said. "The local attitude has been quite hostile. I understand that gambling is an economic activity, but I wish they could at least start investigating on these Singaporeans involved in the international syndicate.
"To give you an example, they never told us whether he has a criminal record or he is a well-respected person. As far as I am aware, he could be either/or."
A Singaporean police officer declined to discuss the case over the phone, but Tan Giap Ti, a media relations officer with the Singapore Police Force, sent a statement in response to e-mailed questions.
"The authorities in Singapore are assisting the Italian authorities through Interpol in their investigations into an international match-fixing syndicate that purportedly involves a Singaporean, Dan Tan Seet Eng, and have provided information requested by the National Central Bureau Rome," the statement said.
Singapore had also received requests from some European countries and was "facilitating them," the statement said, adding: "Notwithstanding, any assistance or enforcement has to be done in accordance with the country's laws and mutually agreed framework."
Zaihan Mohamed Yusof, a reporter for The New Paper, a daily newspaper in Singapore that has covered the match-fixing cases extensively, said he believed Mr. Tan was still in the country.
"He's comfortable here," said Mr. Zaihan, perhaps the only journalist who has interviewed Mr. Tan. (He described Mr. Tan as a "regular Singaporean — he sounds like any guy you might run into at a bus stop or something.") "His resources are here. His money is here."
Much of the evidence against Mr. Tan comes from his former associate Wilson Raj Perumal, a Singaporean arrested in February 2011 in Finland for match-fixing. Mr. Perumal served one year of a two-year sentence in a Finnish prison and was then extradited to Hungary, where is being questioned by investigators.
Through his lawyers, Mr. Perumal sent a note to Mr. Zaihan suggesting that Mr. Tan had set up his arrest.
"Seeking police assistance is a violation of code No. 1 in any criminal business," Mr. Perumal wrote. "Dan Tan broke this code and stirred the hornet's nest."
Arranging the Game
The Italian authorities said Mr. Tan landed in Milan on May 4 and returned to Singapore on May 17. Investigators connected his stay with the coming match at Stadio Olimpico Carlo Zecchini between Reggina and the host team Grosseto, two squads in Serie B, Italy's second-tier league.
The Grosseto players were staying at the Hotel Fattoria Principina, near Grosseto. Mr. Gegic, the former Serbian player who worked as a collaborator under Mr. Tan, according to investigators, was at the Hotel Granduca in Grosseto from May 21 to May 22. Alija Ribic of Croatia, another of the so-called Eastern men, was also at the Hotel Granduca, from May 21 to 23.
In the days leading up to the game, Mr. Saka and Mr. Gegic discussed by phone the various ways they wanted the game to unfold, investigators said. Mr. Saka and Mr. Gegic wanted Grosseto to lose the match. They wanted at least a two-goal difference in the final score. They wanted at least three total goals scored. And they wanted Grosseto to avoid allowing any goals in the first 15 minutes of the match.
If the players being bribed made those four things happen, they would be paid 100,000 euros. The syndicate would make much more by wagering on these aspects of the match.
On the day of the match, May 23, Mr. Gegic exchanged 25 text messages with the Grosseto player Filippo Carobbio. Mr. Ribic and Mr. Gegic called each other eight times that day, including once when Mr. Ribic said there was nothing to worry about.
Soon after, Mr. Saka called Mr. Tan and told him that everything was going according to plan.
But in the closing moments of the match, with Reggina leading, 2-1, the referee awarded a penalty kick to Grosseto. Grosseto scored, making the final score 2-2. Only two of the syndicate's four demands had been met.
Mr. Ribic told Mr. Gegic on the phone that they had lost half of their money in their wagers — but the corrupt players had lost it all. They would not receive their 100,000 euros.