Michel Platini was spotted arriving at the Swiss Attorney General's office with his lawyer on Monday as the former head of UEFA is questioned over a €1.8million (£1.6m) payment from FIFA in 2011.
Platini, who was added to the investigation into the payment earlier this summer, was summoned to Bern by prosecutor Thomas Hildbrand.
He made no comment as he walked into the building on Monday.
Former head of FIFA Sepp Blatter is to questioned at the Attorney General's office on Tuesday. Neither have been charged as part of the investigation.
The case was opened in 2015 and the 65-year-old Frenchman insists that he is being persecuted by FIFA.
‘'After five years, it is quite possible that FIFA will continue to harass me through complaints with the sole aim of keeping me out of football and smearing my reputation,'’ Platini said in June.
The 2011 payment to Platini, given by FIFA for an advisory role completed in 2002, was ‘validated by the finance commission', according to Blatter, 84, who has a year left on his six-year ban from football.
FIFA saw the 2002 pay-out as a ‘disloyal payment' and both Blatter and Platini were suspended in 2015 from ‘all football-related activities', a decision the latter appealed at the Court of Arbitration for Sport, the Swiss Federal Court and then the European Court of Human Rights. Platini's ban was reduced to four years.
The investigation into the payment is ongoing on suspicion of ‘complicity in unfair management, embezzlement and forgery in securities'.
Both Platini and Blatter have denied any wrongdoing in the payment.
This article was most recently revised and updated 2 years ago