Despicable people. Really glad they have been prosecuted and the women rescued, though what a harrowing experience for the women that has affected them for life.
Yes I'd imagine it's a lot easier for traffickers to operate using the EU free movement.
I would also hope that being in the EU would enable the police forces to cooperate more easily across countries and capture and prosecute gangs that are operating from different regions.
There really needs to be more efforts from governments to promote awareness of sex and other types of trafficking in these countries and dissuade people from using any 'agents' that claim they can find them jobs and a better life.