Sex Tourism: ABC News Goes Undercover

April 5, 2010— -- Federal law enforcement sources tell ABC News that the FBI and customs officials are investigating allegations that some fishing and hunting tour businesses are arranging sex with children for American men overseas.

ABC News wanted to know what tour operators offer and whether they market an illegal sex trade?

Wearing hidden cameras, we entered a convention, sponsored by the Dallas Safari Club, where tour companies sell top-dollar hunting and fishing trips all over the world -- some with promises of great parties and beautiful women.

"I mean, it's a third world country and you can do whatever you want," one tour operator told us. "You know if you want to do a party it's not like here—you can't touch, you can't look—you can do whatever the f**k you want."

Said another, "It will start off with six [young women], then it will be twelve, and then it'll be eighteen and then you guys will be just retreating. I'm serious."

But we've heard it's not just women on offer; it's also young girls.

We found one operator who, after at first refusing, tells us when we catch up with him the following day that he can make it happen.

"We'll float the idea to my guy that's going to take care of this thing for you and he can get it done," he says. "I know…he can get that done. But it's probably going to be…it's going to have to be real stealthy…in other words, I don't know…and I'm not saying anything but something is going to happen."

Federal investigators are looking into possible child sex abuse on tours from Central and South America to Africa.

Phil Marsteller, who operates fishing tours in Brazil, says abusing minors has become a cancer on his industry.

"What better way to get away from your wife and go be the -- you know, have the Jekyll and Hyde personality and go do something else than going on a fishing trip to the Amazon that's viewed as family friendly," he said.

The offenders aren't who you might expect. "You're talking about business people, doctors, lawyers, politicians," says Marsteller. "You know, people with lots of money."