The 'Barcagate' scandal goes right to the top of the world's biggest soccer club. Here's what led to Barcelona's stadium being raided and its former boss getting arrested.

• "Barcagate" refers to an alleged smear campaign run by former Barcelona president Josep Maria Bartomeu and his administration.
• Bartomeu's regime is alleged to have hired a company to create fake social media accounts and criticize current and former players.
• Bartomeu, who was arrested on Monday, is also alleged to have misappropriated funds to pay for the campaign.
• He has not been charged with any crime and was released after one night in custody.

Josep Maria Bartomeu, the former president of FC Barcelona, was arrested by Spanish police on Monday as part of an ongoing investigation, believed to be into the so-called "Barcagate" scandal.

Three others, including the club's current CEO Óscar Grau, were also arrested after police searched the Camp Nou to conduct a search and seize operation.

But what exactly led to senior executives at one of the world's sporting powerhouses to be arrested as part of a major police investigation? Read on to find out more about "Barcagate," just one of the litany of problems facing Barcelona in 2021.

What is "Barcagate"?

"Barcagate" refers to an alleged smear campaign run by Bartomeu and his administration against current and former Barcelona players and staff.

In February 2020, Bartomeu and his administration were accused of having paid a firm called I3 Ventures over $1 million to create fake accounts on Facebook and Twitter to attack a number of people involved with the club - most notably Lionel Messi, but also defender Gerard Pique, former manager Pep Guardiola, and others.

It was reported by Radio station SER Catalunya that the accounts had been designed to protect the image of Bartomeu by belittling those who publicly disagreed with him, as well as any potential rivals for the club presidency in the future.

Barcelona admitted at the time to having a relationship with I3 Ventures, but denied any link to the accounts which had attacked Messi and others, which included Alter Sports, Sports Leaks,and Justicia y Dialogo en el Deporte.

Why was Bartomeu arrested?

According to a report by SER, Bartomeu's regime is alleged to have misappropriated club funds by paying up to six times the market value for the services of I3 Ventures dating back to 2017.

The report also says that Bartomeu is alleged to have taken funds intended for the club's academy, La Masia, to pay for the services.

An independent audit in July found that no defamatory campaigns had been launched against any individual and that the services of I3 Ventures were contracted "within market range."

Police have continued to investigate the matter however, first raiding the club's offices in June 2020 before eventually arresting Bartomeu, Grau, and two others earlier in the week.

In a statement published in part by Sky Sports after the arrests, Catalan police said they were regarding "an investigation into alleged crimes related to property and the socio-economic order".

All four men arrested on Monday have since been released, and as of Thursday morning no charges have been brought against any of them

What has Barcelona said?

Following the police search of the Camp Nou on Monday, Barca released an official statement on its website saying the club had "offered up their full collaboration to the legal and police authorities to help make clear facts which are subject to investigation."

"The information and documentation requested by the judicial police force relate strictly to the facts relative to this case," it said.

"FC Barcelona express its utmost respect for the judicial process in place and for the principle of presumed innocence for the people affected within the remit of this investigation."

Barcelona manager Ronald Koeman said Bartomeu's arrest is "not good for the image of the club."

Gerard Pique, one of the players who was a victim of the alleged smear campaign, previously spoke with La Vanguardia about his experience of being discredited on social media.

"As a Barca player, I see that my club has spent money, money that went to criticizing not only people with a historical relationship with the club, but active players - and that is barbaric," the centre-back said back in October.

"I asked [Bartomeu] for an explanation and what he told me was: 'Gerard, I didn't know', and I believed it. Then, later, we see that the person in charge of hiring those services is still working at the club."