Four suspects have been detained, of whom three have been taken into custody. Their nationalities have not been revealed.
The suspected smugglers were in contact with people who recruited the victims via social networks, usually choosing young girls from Russia and Ukraine experiencing financial problems. They offered the girls employment in Spain, for example, that of a hostess or an activities manager at a disco, claiming that the monthly salary would amount to 3,000 euros ($3,433).
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However, upon arriving in Spain, the girls were forced to provide sexual services. According to one of the victims, in case of refusing to do so, they could face a fine of 50-100 euros.
The victim added that the smugglers' leader threatened he would throw the girls on the street without giving them any money.
As searches have been carried out in the club and in a house in Granada, firearms, slightly over 1,000 euros in cash, and marijuana were found there.
A total of 40.3 million people around the world were living in a certain form of slavery in 2016, according to the 2018 Global Slavery Index by the Walk Free Foundation. The share of female slaves exceeded 71 percent.