Usually, there are around 2,800 police officers in the north east region of Spain with a further 1,900 from the paramilitary Guardia Civil.
But the number of officers has now climbed to over 10,000, according to the the Catalan Interior Minister Joaquin Forn.
There are now around 5,300 police officers and 5,000 members of the Guardia Civil amid fears of violent clashes.
In a meeting of Catalonia’s security council earlier this week, which was headed by the regional President Carles Puigdemont, Mr Forn said the figures had been released to him by the central Ministry of the Interior in Madrid.
Mr Forn has previously expressed annoyance by the lack of information coming from the central government in Madrid over the issue of security.
He accused Madrid of sending the extra officers as a way of “altering the order” of the region ahead of the referendum vote and added their presence could be seen as provocative, triggering public order disturbances.
Madrid has been sending members of the security forces to Catalonia for the past month.
Two cruise liners which are currently docked in Barcelona’s port and a third in Tarragona are housing several thousand members of the Guardia Civil.
The liners have since been a target of ridicule for independence supporters due to one of the liners in Barcelona being decorated on the outside with the Warner Bros cartoon character Tweety Pie – known as Piolin in Catalonia – who has since become a sort of unofficial emblem of what Catalans see as their struggle for independence.
Not all the extra members of the Guardia Civil are being housed in the three liners with around 1,000 officers being housed in various barracks, such as the one in Manresa, which are dotted around the region.
A number of the Guardia Civil have been transferred from Andalucía in southern Spain where they were waved on their way by those opposed to the referendum with shouts of “Go get ‘em!”
Previously Madrid had moved to take over control of the Mossos d’Esquadra, Catalonia’s regional police force, a move that was strongly resisted by Mr Forn and the force itself.
Orders have since been issued to Mossos to block the polling stations from opening on October 1, although it remains to be seen if the force will implement the directive.