Six Fifa officials, including Vice-president Jeffrey Webb, have been arrested on suspicion of corruption in dawn raids at a Zurich hotel ahead of Friday’s presidential election.
The members of the world governing body were held by Swiss police at the US Department of Justice’s request.
They are suspected of having received bribes totaling millions of US dollars, the Swiss authorities said.
The FBI and US Department of Justice will hold a news conference later.
Fifa president Sepp Blatter, who is seeking a fifth term in charge of the organisation when he stands for re-election on Friday, is not one of those arrested.
But Vice-president Webb, who is also head of the North America, Central America and Caribbean football federation, is among those held, according to BBC Radio 5 live’s sports news correspondent Richard Conway, who is in Zurich.
Eduardo Li of Costa Rica, Eugenio Figueredo of Uruguay and the Brazilian deputy FA chief Jose Maria Marin were also taken away.
Members of Swiss law enforcement were still present in the hotel at 0800 BST but the main activity and arrests seemed to be over.
Li was due to join Fifa’s executive committee on Friday, while Marin, who was led out of a side exit, is a member of Fifa’s club committee.
The officers were carrying his black suitcase and some of his possessions in plastic bags.
A high-level meeting of Fifa officials is now under way at their headquarters and a news conference is expected at 1000 BST.
Swiss authorities began their operation to arrest the Fifa officials at the five-star Baur au Lac hotel, pending extradition to the US, early on Wednesday.
The Swiss Federal Office of Justice (FOJ) said those held were being investigated “on suspicion of the acceptance of bribes and kick-backs between the early 1990s and the present day”, totalling “more than $100m”.
Fifa general secretary Jerome Valcke briefly visited the hotel on Wednesday morning but declined to comment
A Fifa spokesperson said: “We have seen the media reports and are seeking clarity in this matter. We will make no further comment at this stage.”
Blatter is to go head-to-head against Prince Ali bin al-Hussein of Jordan in Friday’s presidential election.
Prince Ali and his advisors will meet on Wednesday morning to discuss the impact of the arrests on the upcoming vote.
The New York Times reports plain-clothed police officers took the room keys from the reception of the Baur au Lac hotel and headed upstairs to the guest rooms.
It said the operation was carried out peacefully.
