Transcript for Undercover for Alleged Underage Prostitution Raid at Colombia Villa
our sex turnism takedown. The operation has been going for months, and the stakes are high. Will it work? Once again, here's ABC's David Wright. Reporter: In Colombia, the bachelor party is on. A parade of pretty young girls, ready to work. 30 in all. Many of them are very young. The allege D traffickers, true to their word. But this isn't a typical bachelor party. Upstairs, the authorities are waiting for the right moment to drop the hammer. Tim is in on the sting. He's the leader of operation underground rail road, who works with local authorities to catch pimps that sell underage girls for sex. Your name is Andrea? Or that's what we'll call you? Her parents have no idea she's a prostitute. She's 17, but has been working for six years. You started at the age of 11. Do the men pay for more young girls? Almost twice the price. She says she wishes she didn't do this. At the party -- He brought like 100 girls. I'm missing three, because they're so late. 100 girls. 100! Reporter: Some of the girls are just 14 years old. Of course, absolutely. They're giving eyes out, right. You know, trying to flirt with guys. Reporter: One of the alleged traffickers singles out one girl. She's 14 years old. Reporter: In order for the Colombians to prosecute, there has to be no doubt. Does she do everything? I have to talk to her. Oral sex? There's not going to be any problem? Reporter: And money has to change hands. This is the good part. Let me see. Reporter: Cold, hard cash right there on the table. This is the crucial moment investigators need to seal the deal. The man on the left there is a worker for the cti, Colombia's version of the FBI. He gives the code word. The bust is on. What the heck? Reporter: Federal police to arrest the five alleged traffickers, and social workers to help the girls. Tim is playing his part, demanding to see his lawyer. So, is it worth it? Worth what? Reporter: To bring underage girls here. I lied to him about it. Reporter: He says it's all just a misunderstanding. So, are you lying then or now? I wanted him to be happy with the girls I found. But no, there's not a single girl here that's underage. Reporter: He says he has a daughter that's 15 back in the states. How could you do that? I'm not looking for young girls. Reporter: You think this is a total mistake? Yes. You know why? Because I did not look for young girls underage. Reporter: But you seem to have brought some. Please, check their I.D.S. Reporter: I think they'll check more than than I.D.S. Out by the pool, the social workers are one by one checking I.D.S. Can I take my wig off? It's okay. Reporter: Many of the girls are afraid they're being arrested. This is their livelihood. For some of them, their main concern is to get paid for a night's work. Not being arrested. Some of them looked really terrified. I talked to a few of them and asked how old they were. Some were 12, 13, most were 14. One started to cry, and I started to cry. It's been very -- Reporter: Your heart goes out to them, huh? For these girls, it's a long road ahead. Over the next few days, social services did interviews with them and their families. What makes me sad is that yes, we got four traffickers. And I hope they fry. But what makes me sad is I think so many of these little girls, they don't know any different. Reporter: And end up back out on the street? Yeah. Reporter: You think you did some good tonight? I know we did, but so much more needs to be done. Reporter: Any underage girl will be taken to a foster program to make sure they get the care they need. It's bittersweet. It's so horrific. I see my own children in this. Reporter: But anyone of age is free to go. And in so many cases, even the youngest girls return to the streets. And sure enough, we saw some of the same girls, the ones that could prove they were under 18, back on the street. Tonight's raid, just an inconvenient ordeal. David Wright, for "Nightline." And they told us they return to Colombia in the fall, freeing 55 victims from sexual slavery.
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