Photo credit: AFP.

A Singaporean accused of leading the world’s largest soccer match-fixing syndicate was rearrested in the city-state Tuesday about a week after he was freed by the country’s highest court, local media reported.

Businessman Dan Tan, who was arrested in Sept. 2013 but never tried, was released on Nov. 25 after the Court of Appeal ruled that it was “unlawful” to keep him detained because he did not pose a danger to public safety in the city-state. But on Tuesday, police said they had rearrested Tan, also known as Tan Seet Eng, for investigations into suspected involvement in criminal activities, the Straits Times newspaper reported.

No further details were given.

Tan’s earlier release was criticized by soccer’s world governing body, FIFA, and other analysts as a blow to efforts to rid the global sport of corruption. FIFA said through its spokesman last week that it was “very disappointed” with Tan’s release “given the gravity of his past activities relating to match manipulation.” After Tan’s first arrest in 2013, the then-Interpol chief Ronald Noble said the Singapore-based ring was the world’s “largest and most aggressive match-fixing syndicate, with tentacles reaching every continent.”

Singapore’s ministry of home affairs, under heavy international pressure, had invoked a special anti-gangster law against Tan, 51, after it became difficult to find enough evidence and witnesses to file criminal charges. The law allowed the home affairs ministry to order the detention of suspected criminals without trial subject to an annual review. But the three-judge Court of Appeal, Singapore’s highest legal authority, said that while match-fixing was “reprehensible and should not be condoned”, Tan’s alleged acts “all took place beyond our shores” and no evidence was presented to show that potential witnesses were being intimidated.

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Chris Eaton, the Qatar-based executive director for sport integrity of the International Center for Sport Security, had also criticized the court’s ruling and urged Singapore to update its laws.

“Dan Tan Seet Eng wrought enormous damage in the global sport of football. Evidence of it abounds internationally,” Eaton told AFP last week.

Persistent allegations that affluent Singapore is a major hub for match-fixing have stained its reputation as one of the world’s least corrupt nations. Singaporean Rajendran R. Kurusamy was sentenced to four years in jail in September for conspiring to rig a Malaysia-East Timor match at the Southeast Asian Games in Singapore in May. In July 2014, Singaporean nightclub owner Eric Ding was jailed for three years for providing prostitutes to three visiting Lebanese referees in an attempt to fix future matches. Police say global match-fixing generates billions of dollars a year in revenues, fueled in part by the popularity of online betting on match results and more minor game statistics.

In a book about Singapore’s deep links with global match-fixing, local investigative journalist Zaihan Mohamed Yusof said authorities swooped on Tan’s gang after uncovering plans to rig qualifiers for the 2014 World Cup in Brazil. Experts have said that easy international transport, a passport accepted around the world and fluency in English and Mandarin have helped Singaporean fixers spread their influence abroad with the support of external investors, most believed to be from China.

Tan first came to prominence when fixer Wilson Raj Perumal, also a Singaporean, was arrested and jailed in Finland in 2011 for fixing top-tier games there. Perumal, now assisting match-fixing investigators in Hungary, had told prosecutors he was a double-crossed associate of Tan.