The French handball league (LNH) said that the Karabatic bothers, Olympic champion Samuel Honrubia, Mladen Bojinovic, Dragan Gajic, Primoz Prost and Issam Tej had been found guilty of having "directly or indirectly, placed bets on the result of the game".
The players, all members of the Montpellier team at the time, have been under formal investigation since October on charges of fraud and match-fixing. They have denied any wrongdoing.
According to the prosecutor, a total of 87,880 euros were placed in bets on a first division game between Montpellier and Cesson-Sevigne last May, 40 times the usual amount for this kind of match.
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Most of the bets were placed around the same time of day and 99.94 per cent were put on struggling Cesson-Sevigne to lead at halftime, the prosecutor said.
If found guilty, the players risk prison sentences of up to five years and fines of 75,000 euros.
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