Police in Spain's Canary Islands have broken up a human trafficking gang which forced Eastern European women into prostitution.
Spanish police arrested 33 people, including 15 Bulgarians, authorities in Spain and Bulgaria said.
The gang had smuggled up to 500 women, mostly from Bulgaria, promising them waitressing jobs in luxury locations.
The arrests followed a two-year investigation launched after two trafficked women tipped off police.
Bulgarian police chief Valentin Petrov named the suspected ringleader as Kiril Djalev, alias Kiko, 35, from a small town in southern Bulgaria.
"Young and beautiful girls in difficult financial circumstances were lured with promises of honest, legal and well-paid jobs on the Canary Islands," the Bulgarian Interior Ministry said.
"Some of the women had an idea about what the job could entail, but not to its full extent - an absolute limitation of freedom and sexual slavery to enrich their bosses," it added.
"The jobs were advertised on the internet," Mr Petrov said.
The traffickers transported the women to the islands of Fuerteventura and Lanzarote, where they took away their passports and forced them to work as prostitutes in bars and clubs, often subjecting them to violence, police said.
Some of the women were forced to work as sex slaves in the ringleader's own luxury villa and on his yacht, Bulgarian media report.
The operation against the trafficking gang was conducted jointly by Spanish and Bulgarian police, Mr Petrov said.
In May, Bulgarian police participated in an Italian-led crackdown on child trafficking in Europe.
Organised crime in Bulgaria has raised concerns in the EU, which the country is set to join on 1 January 2007.