'Walking Dead' alum helps rescue children in Colombian sex trade

During her three seasons as Andrea on The Walking Dead, Laurie Holden killed a lot of zombies, annoyed a lot of viewers and shot Daryl. However, now the actress has a new role, fighting a real-world threat: child sex trafficking.

ABC's Nightline reported this week on Operation Underground Railroad, an organization founded by former CIA agent and Homeland Security investigator Tim Ballard that specializes in cases involving child sex trafficking. For a recent sting operation in Cartagena, Colombia -- launched in cooperation with that country's government -- Ballard relied on "a ragtag group of volunteers" to help stage a bachelor party, with the goal of rescuing child prostitutes brought to the event and arresting the traffickers.

Among the volunteers was Holden, who donned a brown wig for her role in the sting. "I talked to a few of them and asked them how old they were, and some were 12, some were 13, most were 14," the actress told Nightline. "One of the girls came and embraced me and started to cry, and then I started to cry. It's a very ...," she added, choking up. "What makes me sad is, yes, we got four traffickers, and I hope they fry, but what makes me sad is that I think so many of these little girls ... they don't know any different."

EXCLUSIVE: Firefly: The Sting OGN First Look Sees A New Heist Team Forming

More in Comics