American financier Jeffrey Epstein pleaded not guilty on Monday to charges of sex trafficking as prosecutors accused him of luring dozens of girls as young as 14 to his luxury homes in New York and Florida and paying them for sex acts.

An indictment unsealed in federal court in Manhattan accused Epstein, 66, of arranging for girls to perform nude "massages" and other sex acts and paying some girls to recruit others, from at least 2002 to 2005.

"The alleged behavior shocks the conscience and while the charged conduct is from a number of years ago, it is still profoundly important to the many alleged victims, now young women. ... They deserve their day in court. United States Attorney Geoffrey Berman

"The alleged behavior shocks the conscience and while the charged conduct is from a number of years ago, it is still profoundly important to the many alleged victims, now young women," United States Attorney Geoffrey Berman said at a press conference. "They deserve their day in court."

Epstein was known for socializing with politicians and royalty, with friends who have included US President Donald Trump, former president Bill Clinton and according to court papers, Britain's Prince Andrew. None of these people were mentioned in the indictment.

According to the indictment, the former hedge fund manager "intentionally sought out minors and knew that many of his victims were in fact under the age of 18, including because, in some instances, minor victims expressly told him their age."

Epstein found his underage victims by paying some of the girls he abused to recruit other girls they met at house parties or the mall. But Epstein also allegedly found victims through a man named Jean-Luc Brunel. He's a modeling scout from France who's accused of bringing girls from overseas to the US under the pretense of getting them modeling contracts. Brunel has denied the claims.

The World's Marco Werman spoke to Anita Teekah, the senior director of the anti-trafficking program Safe Horizon in New York City, about how people can be lured into trafficking by modeling contracts.

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Marco Werman: Have you seen sex traffickers posing as modeling scouts before? Or modeling scouts doing things that you thought counted as sex trafficking?

Anita Teekah: We have had clients who were enticed through modeling recruiters and either they had a lot of exploitation of trafficking within the modeling industry as models or they were sex trafficked after thinking they were going to enter into the modeling industry.

And how common is this kind of deal?

We don't have hard numbers on how many individuals are currently being trafficked or exploited within the modeling industry. A lot of human trafficking individuals don't self-identify as human trafficking individuals because they don't know that what they're experiencing is actually human trafficking. And so this can be in the form of being trafficked and forced to provide labor as a model or to be forced to engage in commercial sexual activity.

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If you're recruited though, to model, how are you then forced to model?

So, for example, you might find that if you were told you would have eight-hour work days and you would have rest periods and you would earn say, $1,000 a week, you might find that you're asked to work 16-18 hours a day, you don't earn the amount that you were told you would earn and you're not given adequate food or other nutrients in order to survive. And so, the working conditions that you're promised versus what you're actually presented with once you engage in the work can be two very, very different things.

Got it. What part of the world do these victims tend to be from?

So it really depends. But it tends to be Eastern Europe or Mexico, Central America.

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How did the sex traffickers actually find their victims?

It can be any number of ways. Now, with online internet recruiting, if you put up a website and you have ads saying we are hiring for models and the pay would be this much and you get to travel internationally and you would make this much money — that you can send home to support your family — that's clearly very enticing, especially for individuals who are coming from a more economically unstable background. For the sex [trafficked] clients that we have, a lot of times they can be recruited through the guise of romantic relationships. And so, once there is a sufficiently deep emotional attachment, then the trafficker will say, "OK, well, actually, I need you to do a favor for me. I need you to do this modeling contract. You can earn some money that would really help me out, that would help your family out." And so the individual will agree to do whatever the person is asking them to do and then they find out that it's really something very different — that it might turn out to be a sex trafficking situation.

The modeling industry seems like it lends itself to this in a big way. You've got young women, detached from their parents, flying far away. Is this industry prone to this kind of thing and what are they doing about it?

It depends on what the legal framework requires. If we're talking about the United States, state-by-state they may have their own legal requirements to ensure that there is no labor exploitation and trafficking of models in the industry. If the models are being taken from country to country, then it depends on that particular modeling agency and whether they are beholden to particular country guidelines as you're moving from Paris to Milan and so on.

But within the fashion industry overall, we've seen trafficking and we've seen exploitation. We see it in the apparel industry, with the making of garments. We see it in modeling. We see it in the picking of cotton, to the creation of the thread and the silk, to sewing the T-shirts. And so, the more people you have involved, the more opaque it becomes to see who is doing what, who is responsible for what and where does the ultimate liability lie.

This interview has been condensed and edited for clarity. Reuters contributed to this report.