A criminal case against FIFA president Gianni Infantino was opened on Thursday by a Swiss special prosecutor.
The case is connected to a meeting Infantino had with the Swiss attorney general.
The special prosecutor, Stefan Keller, closed an investigation into two complaints involving Infantino and Swiss attorney general Michael Lauber after turning up "elements that make up reprehensible behaviour."
Lauber announced his resignation last week.
Keller opened a criminal case against Infantino as well as Valais prosecutor Rinaldo Arnold, and has sought authorisation to open a legal case against Lauber, too, according to a statement from the Swiss authority overseeing the federal prosecutors office.
Keller, a legal expert named to the post of special prosecutor on June 29, found that possible infractions included abuse of public office, breach of official secrecy, "assisting offenders" and "incitement to these acts," the supervisory authority for the office of the attorney general said in its statement, adding other criminal acts and proceedings could also be considered.
Suspects in such cases benefit from a presumption of innocence in Switzerland until legal proceedings are completed.
Lauber offered to resign on Friday only minutes before a federal court upheld allegations that he had lied about a meeting he had with Infantino during a sprawling investigation into corruption in football. It came in response to Lauber's appeal against being disciplined in March for misconduct.
The internal disciplinary case against Lauber focused on a meeting he had with Infantino in June 2017 at a hotel in Bern, at which the prosecutor took no notes. They later both said they could not recall their discussion at what was their third meeting in a 15-month period.
"On the basis of general life experience, such a case of collective amnesia is an aberration," the federal court ruling said last week.
Lauber is set to join former FIFA president Sepp Blatter and former UEFA president Michel Platini as senior officials in Switzerland who lost their jobs because of an investigation that began in November 2014.
"FIFA acknowledges the decision of the Swiss special federal public prosecutor in opening an investigation regarding the meetings involving the FIFA president Gianni Infantino and the Swiss attorney general Michael Lauber.
"FIFA, including the FIFA president, remains at the disposal of the Swiss authorities and will, as we have always done, co-operate fully with this investigation.
"'People remember well where FIFA was as an institution back in 2015, and how substantial judicial intervention was actually required to help restore the credibility of the organisation,' said the FIFA president earlier today.
"'As president of FIFA, it has been my aim from day one, and it remains my aim, to assist the authorities with investigating past wrongdoings at FIFA. FIFA officials have met with prosecutors in other jurisdictions across the world for exactly these purposes.
"People have been convicted and sentenced, thanks to FIFA's co-operation, and especially in the United States of America, where our co-operation has resulted in over 40 criminal convictions. Therefore, I remain fully supportive of the judicial process, and FIFA remains willing to fully co-operate with the Swiss authorities for these purposes.'
"In addition, as far as FIFA is concerned, and as previously communicated on Thursday 25 June 2020 by the FIFA president: 'To meet with the attorney general of Switzerland is perfectly legitimate and it's perfectly legal. It's no violation of anything. On the contrary, it is also part of the fiduciary duties of the president of FIFA.'
"When Gianni Infantino was elected for the first time four years ago, FIFA was involved as a damaged party in more than 20 proceedings in Switzerland alone.
"'There was a mountain of questions,' the FIFA president also added during the council press conference. 'So it's legitimate to offer to contribute to the Swiss attorney general about the clarification of these events, hoping that those who have done criminal acts and damaged FIFA will be held to account for that."