Paris - The president of French league leaders Olympique Marseille was still in custody Wednesday on suspicion of transfer fraud as investigators stepped up a parallel inquiry into match-fixing involving other clubs.
Fifteen serving and past Marseille officials, including president Vincent Labrune and two of his predecessors, were detained in raids on Tuesday. Football agents are also among those seized.
Police are looking into transfers made in recent years, including that of key striker Andre-Pierre Gignac from Toulouse in 2010. Suspicions of extortion, money-laundering, fraud and conspiracy with underworld gangs are being investigated, police sources told AFP.
The sources said gangland figures were suspected of receiving commission from several major transfers, including that of French World Cup player Gignac and Senegalese international Souleymane Diawara. Diawara joined in 2009 from Bordeaux and left this year for Nice.
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No player has been implicated in the inquiry. But documents on the Gignac deal were among papers seized in raids on Marseille's headquarters in recent weeks.
The club insisted in a statement that the investigation was focused on past management teams and that it was merely helping the inquiry.
The detention of Labrune, alongside his managing director Philippe Perez and predecessors Jean-Claude Dassier and Pape Diouf, is still an embarrassment to the club as they enjoy their most successful season since they last won the title in 2009-2010.
The club have won nine Ligue 1 titles and are looking to equal St Etienne's record of 10.
Marseille's fans are exasperated at the new blow to the image of one of France's best-supported clubs.
The club were stripped of a Ligue 1 title they won in 1993 after being found guilty of "buying" a match against Valenciennes.
Second division side Nimes are at the centre of a separate inquiry into the fixing of games last season.
Police are investigating whether Nimes owner, Serge Kasparian, approached other teams to fix results so that his side were not relegated to the third division.
Police have detained the president of Caen, Jean-Francois-Fortin, whose team played Nimes on May 13. The 1-1 result meant Nimes stay in the second division and helped Caen to promotion to Ligue 1.
Dijon have also been raided. Nimes' current president Jean-Marc Conrad and Dijon coach Olivier Dall'Oglio are among some 10 people detained.