Police investigating player transfers arrested Quique Pina in the south-eastern region of Murcia, while raids were carried out in Andalusia, including at the offices of Cadiz.
They also raided offices at Granada, the second-tier club Pina served as president between 2009 and 2016 before moving to Cadiz.
An entrepreneur and player agent, Pina also used to own Ciudad de Murcia, a club that rose to the second division before going out of business in 2007.
Cadiz, currently second in the second division as they look to return to La Liga for the first time since 2005/06, confirmed that raids were being carried out at their offices but insisted they were not connected to the club itself.
"The raids...are related to the professional activity of the club but in no way is the club the object of these raids," read a Cadiz statement.
Granada, currently eighth in the second division, said the police operation was related to an investigation into the former board of the club up to 2016.
They are now under Chinese ownership.