Former Barcelona president Josep Maria Bartomeu was released on Tuesday, a day after he was arrested in a probe related to allegations of improper management and business corruption.
A Barcelona court said in a statement Bartomeu, president between 2014 and 2020, and his former adviser Jaume Masferrer, had made use of their right not to testify in court and the judge had agreed to their provisional release.
Bartomeu was among four people connected with the club arrested on Monday in what Catalan police called "an investigation into alleged crimes related to property and the socio-economic order".
Barcelona CEO Oscar Grau and legal services director Roman Gomez Ponti were detained and later released on Monday while Bartomeu and Masferrer spent the night in a Barcelona police station.
The club's offices at their Camp Nou stadium were one of five properties searched by police during the operation.
The operation is in connection with last year's 'Barcagate', in which club officials were accused of launching a smear campaign against current and former players, who were critical of the club and Bartomeu.
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Barcelona had denied accusations that they hired and overpaid a company to make negative comments about their own players and opponents on social media in order to boost the image of senior officials.
The company was accused of using fake social media accounts to discredit opposition figures when they expressed views that went against the club.
Some of the figures supposedly included players such as Lionel Messi - who was unhappy and unsettled at Barcelona at the time - defender Gerard Pique, as well as former head coach Pep Guardiola. The club later released an independent audit report showing that there had been no wrongdoing.
Bartomeu and his board of directors resigned last year amid fallout from the controversy surrounding Messi and ahead of the upcoming presidential elections, which are to be held in less than a week's time.
Presidential candidate Joan Laporta said Monday's events would cause "enormous harm to the image of our club".
He said: "Facing what happened today with the raids at the club's headquarters and the detentions of Barca's ex-president Josep Maria Bartomeu and other executives of the club, our team want to express our utmost respect for the actions conducted by the judiciary and police authorities as well as utmost respect towards the principle of presumption of innocence.
"We are deeply saddened by these events that cause enormous harm to the image of our club."
A club statement on Monday said they were co-operating fully with the investigation, stating: "Regarding the entry and search by the Catalan Police force this morning... FC Barcelona have 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. FC Barcelona expresses 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."
Koeman on Xavi rumours: I haven't talked to anybody
Rumours suggest a new club president could bring former player Xavi Hernandez back to Barcelona as head coach.
The former Barca player told FIFA last week "it would be a dream" to manage Barca one day, but added that he respected Koeman and wished the Dutchman well in the role.
Speaking about the rumours, Koeman said: "I haven't talked to anybody. I think we must wait to find out who the next president will be and then learn about his plans for the club and his future technical staff, and then we will talk.
"And if I don't see a good future for myself here then we will have a problem, because I have another year of contract."