Swiss police have raided UEFA headquarters in relation to the contracts between European football's governing body and the Cross Trading company that have been reportedly highlighted in the 'Panama Papers' leak.
Recently elected FIFA president and former UEFA general secretary Gianni Infantino became the latest high-profile footballing figure to be linked to the controversy on Tuesday.
Widely released reports claimed that documents within the 'Panama Papers' - which have been leaked from law firm Mossack Fonseca to the international press - indicated that, during his time as UEFA's director of legal services, Infantino signed off on a deal to sell South American broadcasting rights for the Champions League, UEFA Cup and Super Cup to Cross Trading in 2006.
The papers allegedly show Cross Trading to have sold the rights on at a significant mark-up to broadcaster Teleamazonas.
Neither Infantino nor UEFA are accused of any wrongdoing over the reported rights agreement but both moved to deny any suggestions of improper conduct through separate statements.
UEFA outlined its willingness to cooperate with the authorities on the matter and confirmed police entered its Nyon HQ on Wednesday with full cooperation.
A statement from the organisation read: "UEFA can confirm that today we received a visit from the office of the Swiss Federal Police acting under a warrant and requesting sight of the contracts between UEFA and Cross Trading/Teleamazonas.
"Naturally, UEFA is providing the Federal Police with all relevant documents in our possession and will cooperate fully."
The Office of the Attorney General of Switzerland (OAG), also released a statement on Wednesday.
"The OAG's criminal proceedings are in connection with the acquisition of television rights and are at present directed against persons unknown, meaning that for the time being, no specific individual is being targeted by these proceedings," it read.
"The suspicion is based on the result of findings that have emerged from other proceedings, as well as the corresponding financial analyses carried out by the OAG."
Two Argentine businessmen apparently named in the Panama Papers as having been behind the Cross Trading deal have since been accused by US prosecutors of involvement in the corruption scandal that engulfed world football and eventually led to the departure of Infantino's predecessor at FIFA, Sepp Blatter.
Infantino's Tuesday statement read: "I am dismayed and will not accept that my integrity is being doubted by certain areas of the media, especially given that UEFA has already disclosed in detail all facts regarding these contracts.
"From the moment I was made aware of the latest media enquiries on the matter, I immediately contacted UEFA to seek clarity. I did this because I am no longer with UEFA, and it is they who exclusively possess all contractual information relating to this query.
"In the meantime, UEFA has announced that it has been conducting a review of its numerous commercial contracts and has answered extensively all media questions related to these specific contracts.As I previously stated, I never personally dealt with Cross Trading nor their owners as the tender process was conducted by Team Marketing on behalf of UEFA."