USA Track and Field (USATF) President Vin Lananna has been placed on temporary administrative leave as a Department of Justice (DoJ) investigation assesses bids for several international athletics events.
The USATF said they have learned that reports of a federal investigation into the awarding of the 2021 World Championships have been confirmed.
They also acknowledge that "TrackTown USA and its President, Mr Lananna, were initially contacted by federal law enforcement months ago".
TrackTown USA have been responsible for multiple National Championships and the 2014 World Junior Championships.
Lananna led the Eugene bid for the World Athletics Championships in 2019, where the Oregon city lost to Qatar's capital Doha.
The International Association of Athletics Federations (IAAF) then awarded the 2021 World Championships to Eugene later in 2015.
Lananna denied that the IAAF was presented with a "now or never" deal before awarding Eugene the event without the city having to go through a bidding process.
The IAAF decision, which came five months after Eugene had been beaten to the 2019 World Championships by Doha, was widely criticised, particularly by athletics representatives from Swedish city Gothenburg who had planned to bid for the 2021 event themselves.
All but two members of the 25-strong IAAF Council body, strongly urged by the then IAAF President, Lamine Diack, voted for what was described as "a unique opportunity that may never arise again, whereby public authorities, the private sector, the National Olympic Committee, NBC and a particularly enthusiastic public are joining forces".
The USTAF said that their board have voted to place Lananna on temporary leave as the investigation continues.
"USATF has no reason to believe TrackTown and/or Mr Lananna have done anything wrong and understand that they have been told that they are not a target of the investigation," said Steve Miller, USATF board chair.
"But to avoid any conflict or appearance of conflict of interest in relation to the investigation, the board voted to place Mr Lananna on temporary administrative leave until the Department of Justice investigation pertaining to TrackTown and the 2021 World Championships is resolved."
USATF stated that they are encouraging TrackTown and Lananna, who was elected USTAF President in 2016, to continue cooperating truthfully with the DoJ investigation.
The governing body added that they have not been approached by the DoJ regarding their investigation, but they will reach out to offer their "commitment to cooperate fully".
Michael Conley has been selected to temporarily serve as USTAF President and vice-chair, with the Barcelona 1992 triple jump gold medallist currently acting as the chairman of the USATF High Performance Division.
He was formerly USATF's executive director of elite athlete programmes.
Lananna has claimed he does not believe the board's action to be necessary.
"To be honest, I am surprised and taken aback at the board's decision," he told Reuters.
"I have been committed to track and field and the members of this federation for over 40 years, and I am dedicated to continuing my service to the sport.
"I do not agree that this action was necessary."
The IAAF Council voted in favour of awarding the World Championships to Eugene in April 2015, under the leadership of Diack.
The Senegalese is currently the subject of an investigation by authorities in France, while his son Papa Massata Diack is being investigated over claims he accepted a bribe to help Rio de Janeiro win the rights to host the 2016 Olympic and Paralympic Games.
He is also linked to an alleged scheme to help Tokyo win its bid to host the 2020 Olympic and Paralympic Games.
Papa Diack has been on Interpol’s most wanted list since December 2015, but is sheltering in Dakar as the Senegalese Government refuses to extradite him to France.