Police arrest Josep Maria Bartomeu after raid on Barcelona's Camp Nou

Barcelona’s former president, Josep Maria Bartomeu, his advisor Jaume Masferrer, the club’s chief executive, Óscar Grau, and the head of legal services, Román Gómez Ponti, have been arrested and Catalan police have entered the Camp Nou to seize documentation as part of an investigation into an alleged misuse of funds and corruption.

The arrests are part of a case put together by the investigating judge relating to Barcelona’s hiring of a social monitoring company, I3 Ventures. Via a series of companies, I3 Ventures had been accused of setting up websites and social media accounts that wrote stories defending the president and damaging the reputations of opposition figures and even some players and former players.

Barcelona were alleged to have over-paid for the services, which they were alleged to have done in a series of smaller instalments that did not require authorisation by the board or trigger internal controls. In total, payments to the company are alleged to have added up to €1,107,500 in 2017-18 with a contract signed for the next two seasons worth €947,700, although the services were stopped after the story broke, it is claimed. In each case, the payments made were reportedly under the €200,000 threshold that triggers internal checks.

Barcelona denied any wrongdoing and I3 ventures insisted the accounts publishing negative stories were not theirs. An internal audit carried out on the club’s behalf by PricewaterhouseCoopers cleared them of corruption or defamation, prompting the club to demand that media who had made “defamatory accusations” to “rectify” reports. But the police operation continued, led by the investigating magistrate, Ariadna Gil.

FC Barcelona confirmed that officers from the Mossos d’Escuadra’s Economic Offences Unit were at the stadium on Monday and promised full cooperation.

This is the second time the authorities have seized documentation at the stadium. Although investigators had initially only requested the gathering of documentation, police said they had made arrests.

Cadena SER radio, which uncovered the initial case that prompted the investigation, reported the four men had been arrested on suspicion of “unfair administration, corruption between individuals and money laundering.”

Bartomeu, who was forced to resign as president of Barcelona in October, was arrested at his home. None of the men are expected to be held overnight, but they will be required to give formal statements.

The arrests come in the build up to presidential elections on Sunday, with three candidates competing to run the club: Joan Laporta, Víctor Font and Toni Freixa.

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More than €800m in debt, Barcelona are faced with a financial and institutional crisis. In April, six board members resigned over the way the club was being run not long after the first story broke. That included Emili Rousaud, who Bartomeu appeared to be preparing to be a continuity candidate at forthcoming elections. In an interview with RAC1 radio station, Rousaud was highly critical of the way the club was being run.

In June, Barcelona suspended their compliance officer, Noemi Romero, who was responsible for leading an internal investigation. They employed PwC to carry out an audit. The report, released in the summer, concluded there was no corruption and that what they had paid for social monitoring services was not out of line with market prices.

“We have not found any indication that any instructions [for online content] were made by the directors of the club,” the report said. “FC Barcelona did not order an campaign of defamation against anyone. There was no corrupt conduct.

“We have found no evidence to suggest that anyone from the board of directors has directly benefitted economically as a result of the contacts.”

The report did raise doubts about the way payments for the services were made, referring to a failure to follow protocol.

Police judged an investigation commissioned by the club could not be considered conclusive and continued to pursue the case, leading to arrests on Monday.