Juventus coach Antonio Conte is among a number of individuals being questioned by police in connection with a match-fixing probe in Italy.
Lazio captain Stefano Mauri and former Genoa midfielder Omar Milanetto have also been arrested in connection with the investigation.
Mauri and Milanetto have been held over allegations of "criminal association and sporting fraud", the Italian Football Federation (FIGC) confirmed.
Officers are searching more than 19 homes in Italy and abroad, including those of coaches and players of clubs in Serie A, Serie B and lower divisions.
Police arrived on Monday morning at Italy's pre-Euro 2012 training camp in Coverciano, Florence, to question former Genoa and Juventus defender Domenico Criscito, who is now a player at Zenit St Petersburg.
It has since been announced by the vice-president of the Italian football federation (FIGC), Demetrio Albertini, that Criscito will not be included in Italy's squad for Euro 2012.
Monday's operation is part of an investigation called "Last Bet" carried out by prosecutors in Cremona which focuses on 33 games over the past two seasons, the majority of which were in Serie B.
Earlier this month, the Italian Football Federation released a comprehensive 48-page list naming 22 clubs along with 61 individuals that have been reported to the football authorities in connection with a match-fixing ring and betting investigation.
Seventeen people were arrested by Italian police last year, including Atalanta captain Cristiano Doni.
Atalanta, who had been promoted to Serie A at the end of the 2010-11 season, began the recently completed campaign with a six-point deduction as punishment for match-fixing.
Doni was banned from football for three and a half years by the FIGC's disciplinary committee.