Prosecutors in the southern city of Changwon are expanding their investigation into the nation’s first match-fixing scandal involving K-League professional soccer players. They have already arrested two gambling brokers on charges of bribing two active players in their bid to rig match results and win Sportstoto lotteries.

The brokers allegedly gave 120 million won to a goalkeeper of a K-League club and 100 million won to a midfielder of another team. Investigators said the goalie appeared in four Rush & Cash Cup games between March 16 and May 11 and allowed 11 goals, contributing to his team’s defeat in three matches.

The midfielder played in one K-League Cup game during the period, in which he committed four fouls before being replaced in the second half. His team lost that match.

Prosecutors are questioning eight more players for their possible collusion with the bribed two. Shockingly, among the investigated players is Kim Dong-hyun, 27, a former striker for the Korean national squad who now plays for Sangmu or the Korea Armed Forces Athletic Corp.

The scam came as a big surprise to many soccer fans as it is the first of its kind in the K-League since its launch 28 years ago. However, rumors of match-fixing in pro soccer have circulated since 2008 when police arrested 23 brokers and players from the semi-professional K2 League and the amateur K3 League for rigging games.

According to reports, some K-League clubs identified players who had contacted gambling brokers. But they stopped short of bringing the cases to light, choosing instead to either cover them up or transfer the players to other teams. If these reports are true, the clubs deserve criticism for their lack of courage in confronting a festering problem.

Prosecutors need to investigate these allegations and root out any corrupt element in the K-League. They also need to crack down on operators of illegal online sports betting sites who could be tempted to manipulate match results to make undue gains.

According to reports, there are currently some 500 to 1,000 illegal sites in operation, with many making millions of dollars a year. Their annual turnover is estimated at 4 trillion won. These sites attract people because they allow them to make unlimited bets, as opposed to the 100,000 won limit for tickets issued by Sportstoto, the only company in Korea licensed to engage in the sports betting business.

Clamping down on these illegal sites is not easy because they operate their servers abroad. But letting them continue to operate is leaving professional players of soccer and other popular sports exposed to game-rigging temptations.

Match-fixing makes a mockery of the efforts honest players make to win games. It is also an affront to all sports fans. The standard of Korean soccer and other sports cannot be elevated without terminating attempts to manipulate game outcomes.