Spanish police said they found illegal underground shooting on Wednesday, which were running for arms trading that provided assault rifles and other weapons to addicts.
The officers searched the house in the southern province of Granada and found a site located in three stories underground, Police said in a statement.
Neighbors did not hear the weapons come from the depth of the range, the authorities said.
Police said they first found “illegal firing managing the criminal group” in Spain.
Authorities believe the site was used to check the weapon, which the group provided rings for drug trading, which then used them to protect themselves or attack on opponents.
Police posted a video Operations, showing that officers slowly descend from narrow stairs to the cave, as well as the authorities who collect evidence.
“The operation removed weapons from the streets that could be used to commit extremely serious crimes,” the statement said.
Police said the group offered to sell assault rifles, pistols and automatic pistols, as well as ammunition, bulletproof vests and other tactical equipment.
Officers arrested three people and seized several weapons and more than 60,000 euros ($ 68,000) cash.
Most of the weapon was found buried in an open field, “packed for conservation and ready to use,” police said. Investigators stated that they were already focusing on the repository “because of the strong evidence that there was a firearm check.”
Spanish National Police 
Police said additional arrests were possible.
Also on Wednesday, in a separate operation, Spain's police arrested more than two dozen suspected gang members for growing and trading marijuana. Arrests were made after officers found a video on social media Statement by the Ministry of Internal Affairs.
Spain is the main gateway to Europe for drug trading networks with the former colonies in Latin America and the proximity to Morocco, the main manufacturer of cannabis.