Swiss prosecutors carrying out 25 corruption probes linked to Fifa
Switzerland's attorney general is leading 25 separate investigations into suspected corruption linked to Fifa and World Cup bidding.
The office of Michael Lauber confirmed the scale of "football-related cases" after securing a first conviction since its Fifa probes began in 2014.
Cases were not specified, but criminal proceedings are open against former Fifa officials Sepp Blatter and Jerome Valcke, and some 2006 World Cup organisers including Franz Beckenbauer.
Swiss and US prosecutors worked together on a guilty plea this week from Jorge Arzuaga, a former employee of Swiss private banks from Argentina.
Arzuaga admitted conspiring with former Fifa finance chairman Julio Grondona and others in a money-laundering conspiracy linked to bribes.
Mr Lauber's office said Arzuaga forfeited 650,000 US dollars (£510,000) in "unlawfully obtained" bonuses to the Swiss treasury.
Grondona was senior vice president at Fifa when he died in 2014.
Arzuaga, who worked in Zurich for Credit Suisse and Julius Baer, is due to be sentenced on January 4.
Mr Lauber was invited by Fifa in November 2014 to begin investigating suspected wrongdoing in the 2018 and 2022 World Cup bidding contests, won by Russia and Qatar.
"To date, 178 reports of suspected money-laundering transactions have been received in connection with the football investigations," Mr Lauber's office said.
In May 2015, the scope of Swiss and American co-operation to prosecute corruption linked to Fifa was revealed when seven officials, including two Fifa vice presidents, were arrested in early morning hotel raids in Zurich.
Fifa was also raided for evidence that day.
A further round of arrests, indictments and guilty pleas to US courts were revealed in December 2015. More than 40 football and marketing officials have been indicted or made guilty pleas in the American case.
In Switzerland, authorities are analysing "seized documents containing some 19 terabytes of data", Mr Lauber's office said.