FIFA has confirmed that it will investigate the alleged distribution from its headquarters of an anonymous heavily critical 'dossier' on UEFA President Michel Platini.
The investigation follows a complaint from European football's governing body.
German newspaper Welt am Sonntag reported that the document, entitled "Platini - skeleton in the closet", was distributed from FIFA's headquarters.
The newspaper said it paints an unflattering picture of the former French international and questions his suitability for the role of FIFA President.
The existence of the dossier on Platini, who is hoping to replace outgoing FIFA President Sepp Blatter in February's election, has also been reported in the Swiss media.
"FIFA Secretary General Jerome Valcke has received a letter from UEFA regarding the said subject," said FIFA in a statement.
"In his answer to UEFA, the FIFA Secretary General has confirmed that FIFA is investigating the matter."
In addition to Valcke, UEFA said it had also sent its complaint to Cornel Borbely, a Swiss attorney who is FIFA's independent chief ethics investigator, and Domenico Scala, independent chairman of FIFA's Audit and Compliance Committee and chairman of the ad-hoc election committee.
FIFA will hold an election on 26 February 2016 to choose a replacement for Blatter, who said in June he was standing down from his role in the wake of the corruption scandals that have hit the organisation.
Platini is the current front runner in the election but his relationship with Blatter has deteriorated badly.
Meanwhile, South Korea's Chung Mong-joon said Platini was too close to Blatter to be right for the job.
Launching his bid for the role, Chung told a news conference: "Michel Platini was a great football player, and he is my good friend.
"His problem is he does not seem to appreciate the seriousness of the corruption crisis at FIFA."
Former FIFA vice president Chung said Platini, who has been a FIFA executive committee member since 2002, should have done more to root out corruption.
"Recently, Platini said Blatter is his enemy, but we know the relationship was like mentor and protege, or father and son," the 63-year-old billionaire scion of South Korea's Hyundai industrial conglomerate said.
Former Brazilian player Zico, former Trinidad and Tobago midfielder David Nakhid and Liberian FA chairman Musa Bility have also said they are running in the election.
Jordan's Prince Ali Bin Al-Hussein and South African Tokyo Sexwale are also considering taking part.