Criminal proceedings are open against former FIFA official Sepp Blatter. Sepp Blatter ban presser 20151221

The Swiss attorney general's office has said it is leading 25 separate investigations into suspected corruption linked to FIFA and World Cup bidding.

Michael Lauber's office confirmed the scale of "football-related cases" after securing a first conviction since its FIFA investigations 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 U.S. prosecutors worked together this week on a guilty plea 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.

Lauber's office said Arzuaga forfeited $650,000 (£508,886) in "unlawfully obtained" bonuses to the Swiss treasury.