Jeff Z. Klein offers a detailed report on how international soccer authorities and law enforcement officials are struggling to combat rampant game fixing by what they describe as sprawling networks of organized crime.

Game-fixing scandals are engulfing men’s professional leagues around the world, from Turkey, whose top officials are meeting this week to determine whether the coming season will have to be delayed pending an investigation, to South Korea, where dozens of players have been indicted over the past several weeks. Authorities attribute the apparent burst of fixing cases to sophisticated criminal operations based in Singapore, Malaysia and elsewhere in Southeast Asia.

“Probably 90 percent of the legal and illegal gambling on football around the world takes place in Southeast Asia,” said Chris Eaton, a former Interpol official who for the last year has been head of security for FIFA, soccer’s world governing body. “There they bet on all kinds of matches, particularly European football. So it makes sense that criminal activity would arise there alongside it.”

Concerned about the unyielding waves of allegations, which have prompted questions about the integrity of the sport, FIFA pledged $20 million in May to create a unit within Interpol in Singapore dedicated to rooting out game rigging in Asia. Other investigations are continuing in Hungary, Italy, Germany, El Salvador, Israel, China, Thailand, Zimbabwe, Vietnam and Greece, where the presidents of three top clubs were among 84 people charged with game fixing in recent weeks.