Kofi Appiah from Koforidua, Ghana emails: In order for peace and harmony, l believe a rotating Fifa presidency will go long way in fighting corruption and also there must be limited term of office. For Sepp Blatter is not the world, and the world is not Sepp Blatter. He is salt and has lost his taste.

Michael Walsh in Honolulu, Hawaii emails: At what point will we stop fooling ourselves into believing that sport is not just another form of politics? There is no "integrity" to sport by its very nature. That is why we need to demand stronger regulation of national and international sports associations. We cannot allow their leaderships to be above the law in the name of sport.

As things stand the Fifa presidential election will go ahead on Friday.

Here's our explainer on the process by BBC Sport's John Bennett.

Jeremy Palmer in Barbados tweets, external: Time for England, Germany, Spain, Portugal, Italy, France AND the USA to pull out of #FIFA

Nine Fifa officials and five corporate executives have been indicted for racketeering conspiracy and corruption. Announcing the charges, external earlier, US Attorney General Lorretta Lynch said the corruption was "rampant, systemic, and deep-rooted both abroad and here in the United States".

"It spans at least two generations of soccer officials who, as alleged, have abused their positions of trust to acquire millions of dollars in bribes and kickbacks.

"And it has profoundly harmed a multitude of victims, from the youth leagues and developing countries that should benefit from the revenue generated by the commercial rights these organisations hold, to the fans at home and throughout the world whose support for the game makes those rights valuable."

Image source, Reuters

The BBC's 5 live Sport will run a special programme tonight at 19:00 GMT profiling the head of Fifa.

"There's Only One Sepp Blatter" includes the first ever broadcast interview with his daughter Corrine Blatter (recorded before Wednesday's events).

Colin Edwards tweets, external: FIFA no credibility. Friday vote no credibility. Next 2 world cups no credibility.

Over on the BBC's World Have Your Say Facebook page, external, Tim Norris says: Fifa is clearly a money-making machine. If the bribes are $100 million, then the benefits to the companies offering the bribes is many times that. All decent sponsors should just pull out completely until this whole organisation is cleansed, starting at the very top.

Fifa's current motto is and has been for some time "My game is fair play". Will the criminal investigations unravel the governing body of the world's most popular game?

Image source, Reuters

Among those under investigation is Brazilian Jose Maria Marin, a member of Fifa's club committee

Mr Marin, a former football player, was president of the Brazilian Football Confederation (CBF) from March 2012 to April 2015, and was a member of the 2014 World Cup Committee.

The 83-year-old also had a political career, having joined the Workers Party of Brazil in 2007 and been deputy governor and governor of the state of Sao Paulo.

Fifa turned 111 just last week. An inauspicious start to its 112th year then.

Andrew Jennings, a British journalist who investigated the alleged corruption in Fifa for the BBC's Panorama programme, tells BBC World TV the criminal investigation has been "a long time coming".

The BBC's Imogen Foulkes has written a piece on the strange drive of Sepp Blatter to stay on as Fifa president, amid scandal after scandal.

"Many have wondered how Sepp Blatter can have been in charge of Fifa for so long, amid so many reports of corruption, and yet remain, apparently, untouched.

"One Swiss newspaper jokingly called him 'the dark prince of football, the godfather, Don Blatterone' - but no inquiry has ever revealed proof of his involvement in bribery."

Shaun Kruger in Sao Paulo emails: The world desperately needs transparency from anyone in power.

Vittorio Malagutti, the chief editor of Italian weekly news magazine L'Espresso, tweets (in Italian):, external "Corruption, fraud, money laundering. The sheriff arrives at #Fifa. With a 20 year delay." (BBC Monitoring)

Kevin Hughes in Gwernymynydd, Flintshire, UK emails: How can Friday's vote, which is set to be nothing more than Blatter's coronation, possibly go ahead? Throughout his whole time as Fifa president he has been dogged by scandal and allegations of corruption.

More from the ongoing news conference in Zurich. Mr de Gregorio also says that the Garcia report will be published.

He refers to former US attorney Michael Garcia who investigated the 2018 and 2022 World Cup bids. Mr Garcia left Fifa in December 2014 because it refused to fully publish his findings. Only the report's summary has been released.

@TonyBocock tweets, external: @BBC_HaveYourSay At last a serious investigation into #FIFA What a disgrace for real footballing nations that the USA instigated it!

Mr de Gregorio also stresses that Fifa President Sepp Blatter is not involved in the criminal cases.

The spokesman adds that Mr Blatter is "focused on the congress", but adds that "the stress factor is a bit higher today".

Image source, AFP

Mr de Gregorio also confirms that the 2018 and 2022 World Cups will be staged as planned in Russia and Qatar respectively.