Spanish police said Wednesday they have uncovered an illegal underground firing range they suspect was operated by a weapons trafficking ring that supplied assault rifles and other arms to drug gangs.
Officers raided a house in the southern province of Granada and found the site, which was located three stories underground, police said in a statement.
Neighbors could not hear guns going off because of the depth of the range, authorities said.
Police said it was the first time they had found a “illegal shooting range run by a criminal group” in Spain.
Authorities believe the site was used to test weapons that the group supplied to drug trafficking rings, who then used them to defend themselves or attack rival gangs.
Police released video of the operation, showing officers slowly descending narrow stairs in a cave-like structure as well as authorities collecting evidence.
“The operation has removed weapons from the streets that could have been used to commit extremely serious crimes,” the statement said.
Police said the group offered to sell assault rifles, submachine guns 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) in cash.
Most of the weapons were found buried in an open field, “packed for preservation and ready to be used,” police said. Investigators said they were already targeting the hiding place “due to strong evidence that firearms were being tested there.”
Spanish National Police 
Police said further arrests were possible.
Also on Wednesday, in a separate operation, police in Spain arrested more than two dozen suspected gang members for cultivating and trafficking marijuana. The arrests were made after officers found videos on social media showing the suspects “detonating weapons and flaunting their standard of living,” according to a statement by the Interior Ministry.
Spain is a major gateway to Europe for drug trafficking networks due to its ties to former colonies in Latin America and its proximity to Morocco, a top cannabis producer.
