Andreu Subies, the vice-president of the Royal Spanish Football Federation (RFEF), has been arrested on money laundering charges.
A former president of the Catalan Football Federation, Subies joined the RFEF in May to work with Luis Rubiales' team but has now been detained as part of a police project called 'Operation Soule'.
While the Spanish Civil Guard are now searching a number of offices in Catalonia, the RFEF has issued a statement expressing its "utmost respect for the legal actions" and "commitment to transparency."
They have also indicated that they will conduct their own investigation into the allegations alongside Operation Soule.
According to AS, the accusations against Subies relate to his time working under Angel Maria Villar, who served as RFEF president for almost two decades from 1988 to 2017.
Villar also held vice-president roles for FIFA and UEFA but resigned from his posts last year following his arrest on corruption charges.
Also arrested as part of the Operation is Jose Contreras, whose construction company Tastavins was contracted by the Catalan Football Federation to carry out work on their headquarters.
Works were also carried out Tarragona, Sabadell and Vilafranca and these are under investigation as well. The Civil Guard has not ruled out the possibility of further arrests in the coming hours and days.