The nation's top men's professional basketball league on Tuesday apologized for a match-fixing scandal, a day after an active head coach was arrested under rigging suspicions.

Han Sun-kyo, the commissioner of the Korean Basketball League (KBL), held a press conference to express his regrets for the controversy.

"We recognize this situation as the biggest crisis for professional basketball since the league was launched in 1997," Han said. "We're fully cooperating with prosecutors in their investigation and we will give our utmost best to transform ourselves."

Kang Dong-hee, head coach of the Dongbu Promy, was taken into custody on Monday after a district court in Euijeongbu, Gyeonggi Province, granted prosecutors' request for an arrest warrant. Kang faces charges of violating laws governing national sports promotion. He is the first active coach of a South Korean professional sports team to be arrested for match-fixing allegations.

Han said the KBL will adopt a "zero-tolerance" policy against match fixing in basketball, and added, "If Kang is found guilty, we're prepared to ban him for life."

Han explained that the league is carrying out its own internal investigation into match fixing, saying the KBL will fully cooperate with prosecutors if more suspects emerge.

Prosecutors have alleged that Kang took some 40 million won

(US$36,560) from two gambling brokers on four occasions during the

2010-2011 season in the KBL. They believe Kang deliberately lost a game late in the season, with the Promy having already clinched one of six postseason spots, by resting his usual starting players, ostensibly to conserve them for the playoff run.

Kang has been the head coach of the Promy since the 2009-2010 season. He has denied all fixing allegations surrounding him.

On Feb. 28, prosecutors arrested a broker, surnamed Choi, for allegedly giving Kang cash to fix games. Then on Wednesday this week, they arrested a second broker, a former professional baseball player surnamed Cho, on the same charges.

Prosecutors said Friday that they will expand their investigation into a fourth person who allegedly supplied the two brokers with cash. The person, whose name was withheld, is currently serving a prison sentence for his role in a major match-fixing scandal in South Korean pro football in 2011. He had been convicted of starting an illegal sports betting site and paying six active pro football players cash in exchange for fixing games.

Before Kang's charges surfaced, some KBL teams came under suspicions of losing games on purpose in a bid to secure high draft picks later this year. Similar "tanking" practices aren't entirely uncommon in major U.S. sports, though the KBL has suffered a huge blow to its attendance and television ratings.

In the KBL, six out of 10 teams make the playoffs and the four non-playoff teams each have about a 24-percent chance of getting the No. 1 overall pick. The league recently lowered that percentage to 15 percent, effective starting in the 2014-2015 season, but Han said Tuesday he may further alter the rule so that the lowered percentage will take effect immediately with the upcoming draft in October.

Kang last coached the Promy on Wednesday, a day before facing prosecutors' questions. His assistant, Kim Young-man, took over on the bench on Saturday, and Dongbu has said Kim will coach the team for the remaining three games of the ongoing season.

Kang has said he had personal ties with Choi, one of the arrested brokers, but claimed he'd never taken any money from him.

Kang was Dongbu's assistant coach from 2005 to 2009, and became the team's head coach before the 2009-2010 season. The team has finished second in the league twice on Kang's watch. Last year, Dongbu established new KBL records for most wins in a season with

44 and most consecutive victories with 16.

Dubbed "Wizard on the Court," Kang is also regarded as one of South Korea's greatest point guards, dating back to the late 1980s and the early 1990s, before the launch of the professional league.

He was the MVP in the inaugural KBL season in 1997 and led the league in assists four times.

The KBL is the latest pro sports league in South Korea to be hit with a match-fixing scandal, following the leagues for football, baseball and volleyball.

In earlier match-fixing cases in other sports, players, active or retired, were found to have taken cash from brokers making their bets on illegal sports gambling Web sites.

These sites offer proposition bets, or "prop bets." They place odds on seemingly inconsequential plays, such as the number of free throws made in the first quarter of a basketball game, often with no cap on the amount of wager. It's considered easier for gamblers to fix such minute plays.

The only legal form of sports betting in South Korea is through buying Sports Toto lottery tickets. Sports Toto offers odds on wins, ties, losses and the combined scores between teams. A bettor can only wager 100,000 won per ticket.

Han, the KBL commissioner, claimed match fixing could only take place through illegal betting Web sites.

"I don't think there have been fixing attempts involving Sports Toto," he said. "Those illegal sports gambling Web sites are the real problem. We need stronger penalties against these sites." (Yonhap News)