Belgian prosecutors said on Friday they had charged 19 people, including two soccer referees, soccer agents and the coach of Belgian champions Club Bruges, with fraud or match-fixing.
The offences ranged from criminal organisation to money laundering and corruption, federal prosecutors said.
Nine of the 19 remained in custody, including soccer agents Dejan Veljkovic and Mogi Bayat, charged with having set up schemes to hide fees paid to themselves and to players, and referee Bart Vertenten.
Ivan Leko, the Croatian coach of champions Club Bruges, was among those released, although he is charged with money-laundering. He returned to training on Friday.
I will fight back. This is not the first time I was on zero ... I didn't deserve this," he told the broadcaster VTM.
His club are playing in Champions League Group A with Atletico Madrid, AS Monaco and Borussia Dortmund.
Of the others charged, a number are officials at clubs KV Mechelen and Waasland-Beveren, who played each other on the final day of the regular season in March.
Prosecutors suspect that match, won 2-0 by Mechelen, and one a week before when FC Antwerp beat Mechelen's relegation rivals Eupen 2-0, were fixed. In that game, Vertenten awarded Antwerp a penalty after a foul committed just outside the penalty area.
Prosecutors say Veljkovic colluded with officials and referees to prevent Mechelen being relegated, although the club, winner of UEFA's Cup Winners' Cup in 1988, did in fact go down.
Three months after the national side reached the World Cup semi-final, the news indicating uncomfortably close ties between agents, soccer officials and referees has dominated Belgian media.
Police raided 44 clubs and residences across Belgium on Wednesday, while a further 13 searches took place in France, Luxembourg, Cyprus, Montenegro, Serbia and Macedonia.
Among the nine soccer clubs targeted were Belgium's "big three" of Anderlecht, Club Bruges and Standard Liege. The homes of directors, agents, referees and jewellers were also raided.
Mechelen has denied engaging in any illegal practices. Vertenten's fiancee Hetty Boons told VTM he stood accused of something that he had had nothing to do with.
Bayat's lawyer stressed to Belgian television that his client was not accused of match-fixing or corruption, only of money-laundering.
Leko's lawyer said the only issue to be cleared up was a payment dating from 2015, before he was Bruges's coach, and that there was no way that this could amount to money laundering.
Veljkovic's lawyer, Kris Luyckx, spoke to reporters but did not comment on whether or not his client was guilty of any wrongdoing.
Of four people detained abroad, Belgian authorities have sought extradition for two.
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