This is a rush transcript from "Your World with Neil Cavuto," December 20, 2007. This copy may not be in its final form and may be updated.

NEIL CAVUTO, "YOUR WORLD" HOST: To Phoenix, Arizona, right now, human smugglers exploiting the housing downturn. They're renting homes that are not selling and then turning them into stash houses for illegals, as many as 1,000 of them in Phoenix alone.

My next guest says this is a growing problem. Marcy Forman is the director of Marcy Forman ICE Office of Investigations.

So, what is going on here, Marcy?

MARCY FORMAN, DIRECTOR, ICE OFFICE OF INVESTIGATIONS: Well, smugglers of aliens, opportunists, they will take an opportunity when they see one. And here in Arizona, they see an opportunity where the housing market has suffered, and they are taking that opportunity to rent homes to hide and store smugglers — aliens.

CAVUTO: What do they get out of it?

FORMAN: You have to remember, alien smuggling is a crime that generates a lot of money. And what they're getting is, they are bringing in aliens for a certain cost and then they're bringing them into the United States for another cost.

And the dangerousness in it, oftentimes, these aliens are coming into the country. Certainly, the magnet is working here. And they are being held hostage. And money is being extorted from family members in order to release these individuals.

CAVUTO: OK. So, obviously, this has become a recent trend? Is it because of the real estate correction and, all the sudden, all these homes are available for rent, so they scoop them up, and then they — they shovel these illegals in there? Is that what is going on?

FORMAN: Well, it is a recent trend that ICE has just detected, certainly in partnership with our federal, state and local law enforcement officers.

And it's an opportunity. It's an opportunity where the smugglers can — have seen an opportunity to rent homes in communities that often times are not being under — that are not under scrutiny for crime.

(CROSSTALK)

CAVUTO: What can do you about it? All right, now, every — all these, you know citizens' rights groups say, you can't just knock on a door and say, I suspect you have got illegals here.

How do you track this stuff?

FORMAN: ICE, in coordination with their partners, their law enforcement partners, and, most importantly, with our foreign government partners, where these crimes originate from, we work them. We work them collectively.

We identify vulnerabilities. We identify these organizations, and we go after the organizations, both foreign and in the United States, and we disrupt and dismantle them.

CAVUTO: So, Marcy, how do you do it? If you suspect there are a number of homes in a neighborhood that are harboring illegals, how do you pursue that? You have got a good hunch, hey, look, we hear that there are a bunch of illegals in this home, what do you do?

FORMAN: It's like any other type of criminal investigation.

ICE looks at smuggling as smuggling, whether you're dealing with human beings, drugs, weapons of mass destruction. And you go after them. You use all your investigative techniques, your surveillance techniques. You establish probable cause, and then, working with the U.S. Attorney's Office, you get warrants to go in and look for evidence of a crime.

(CROSSTALK)

CAVUTO: But in other words you need — I'm sorry, Marcy, but you need that warrant, right? You just can't knock on the door on the suspicion of illegal activity?

FORMAN: You know, it's on a case-by-case basis.

CAVUTO: Right.

FORMAN: I mean, you can get a warrant. There are many techniques you can use. You can knock and you can ask for consent. It depends on the circumstances.

CAVUTO: OK.

Marcy, thank you very much. This is a weird phenomenon, but thank you for being on top of it, Marcy Forman.

THIS IS A RUSH TRANSCRIPT. THIS COPY MAY NOT BE IN ITS FINAL FORM AND MAY BE UPDATED.

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