Police announced in January they had made a major weapons haul but only now released pictures and a final tally of the results of their operation against firearms trafficking.
In all, the police have impounded over 9,000 CETME assault weapons of different models; almost 1,000 assault weapons from manufacturers such as Mauser, Bergmann or Beretta; fully working mortar shells minus the explosive charge; anti-aircraft machine guns and pistols from the Star, Llama, Astra and FN companies and numerous revolvers.
The guns and ammunition were seized in January during an operation against firearms trafficking.
Alongside the thousands of arms, authorities also discovered material needed to falsify arms documentation and tools required to change the weapons' identification numbers.
Police also recovered 80,000 euros ($85,000) during the raid.
"The armament was acquired mainly through legally established channels and later reactivated", the organisation said in a statement.
Europol, which supported the operation, revealed the firearms were sold in Spain, France and Belgium.
Police in Spain have unveiled a huge illegal arsenal seized from a gang that was selling weapons across Europe.
Police said the weapons would have had an easy journey onto the black market, and into the hands of terrorists or organised crime groups.
They found loopholes in the European bloc to divert legal firearms into the black market, according to Europol.
Reactivating deactivated weapons is one of Europe's main sources of illegal guns.
The agency said it had seen a significant increase in the number being supplied to criminals since 2014.