This is a partial transcript from "Hannity & Colmes," February 16, 2005, that has been edited for clarity.

SEAN HANNITY, CO-HOST: As we continue on "Hannity & Colmes," I'm Sean Hannity.

Yesterday when we were on the U.S.-Mexican border, I got a chance to examine the massive tunnel, the one that was recently discovered running between the two countries.

Now it is the longest one ever discovered. It runs a half-mile from inside an industrial building in Tijuana to inside an office building in the United States. Customs and border officials said a drug czar leased the building. They set up a fake company inside to hide the tunnel, which was discovered, along with over two tons — that's right, two tons of marijuana.

(BEGIN VIDEOTAPE)

HANNITY: So it looks like an average office building.

FRANK MARWOOD, IMMIGRATION AND CUSTOMS ENFORCEMENT: Right. It's just a commercial building in the area, frequently used for any kind of goods brought across from the Republic of Mexico — produce, any kind of hand made goods. You name it.

HANNITY: Very common. OK. Let's walk inside and I think we see a very different operation going on than what most people would expect.

One of the things, when you found it, it was empty. It was all...

MARWOOD: Right. The way you're looking at it right now, is the way it pretty much before it became a produce business. But as you can see, this is the conference room. And there's no furniture in the conference room...

HANNITY: When were you first tipped off this, as a possibility of this may be going on?

MARWOOD: Our investigation on this particular tunnel has been going on for the last year to a year and a half.

HANNITY: And how many tunnels have you found so far?

MARWOOD: That's a hard thing to answer, because there's so many different tunnels, kinds of tunnels. There a little shimmy holes that go under the border fence.

HANNITY: Right.

MARWOOD: Where literally someone just carves out and goes under.

HANNITY: Right.

MARWOOD: Then you get up to a medium sophisticated kind of tunnel that has electricity, ventilation, power systems through it. And then you get to this kind of tunnel which, as you know, is the longest one we've ever discovered on any border, whether it be Canada or down through here.

HANNITY: And how long is this one total?

MARWOOD: The total length on this one is approximately half a mile from the republic into the United States.

HANNITY: Is it?

MARWOOD: Yes.

HANNITY: Wow. That's a pretty long tunnel.

MARWOOD: It's huge.

HANNITY: And how long do you think that it took them to dig this whole thing?

MARWOOD: We're approximating it took them one to two years to dig it.

HANNITY: And how long do you believe it was operational? What is your intelligence telling you on that?

MARWOOD: We're pretty sure now that we've got the comments from people that we've interviewed, as well as some other evidence to indicate that the tunnel probably was operational right after November. So that means it was open about two months.

HANNITY: All right. So not a big investment considering they spent so much time digging this. They were expecting to get a lot more time out of that.

MARWOOD: Absolutely. This is a huge hit to the cartel.

HANNITY: Let's look in here. And let's just take everybody right inside this tunnel and we'll get a quick look at what this is about here.

You wouldn't expect it, but from here we go right down, straight out across, and it's a half a mile into Mexico.

MARWOOD: Correct. There's a little leg that goes off this tunnel that gets into the main tunnel, and it went almost straight into Mexico. It was an amazing engineering feat for the people who designed it.

Because of course them doing it in a clandestine manner, they don't have the kinds of sophisticated tools, the kind of sophisticated systems to plot. Therefore the fact that they could do it so dead-on shows that they were really, really determined for what they were doing.

HANNITY: Well, that's very interesting because you were telling me that the engineers that have looked at this said it was a real engineering accomplishment.

MARWOOD: Right. There's no doubt that the people that built the tunnel designed it and knew thou do tunneling. The actually workers probably were not as skilled, but the person who designed it, who told them how to do it and instructed them what to do, he was a miner.

HANNITY: So have you been on the other end of this?

MARWOOD: I have been to the other end coming from the Mexican side, not going through the tunnel.

HANNITY: All right. Now, this goes down a half-mile through. But now it's become very dangerous because of the different conditions in there.

MARWOOD: A couple of things and the reason it's dangerous right now. One is although they had completed the tunnel, they hadn't completed all the safety features in the tunnel. All of the shoring from the Republic of Mexico up to this point was not complete.

When the Mexicans hit the location on the south side, there was a tremendous amount of lumber left in that building that they were going to utilize.

The second thing is the pumping systems are not working on the south side any more. We're trying to get as much water out of the north side as we can. And so as a result of that, we're finding that the tunnel is in a situation where we can't, you know, definitely tell you the integrity is there.

HANNITY: You think of all the amount of time, the money, the effort, the resources that go into breaking the law, if they would just concentrate their efforts, if this is a one or two year project just to dig the tunnel to break the law there, you know, the amount of money and energy that could be spent doing something productive. It's amazing how much effort is put into this type of operation for law breaking.

MARWOOD: I think again, and I try to tell everybody that wants to get a concept of this, this is a business. Like any business it's to make a profit. So you're going to limit your liabilities. You're going to limit your losses and you want to increase the cash flow.

The narcotics industry is obviously — within the United States the demand is huge.

HANNITY: Right.

MARWOOD: That's what they're answering.

HANNITY: And what's the next step for this? Do you close it down?

MARWOOD: We'll be doing further testing on the tunnel, and then exactly right. We'll be filling it in, because it is obviously in the legal entry point to the United States and one that homeland security can't tolerate.

(END VIDEOTAPE)

HANNITY: People would just spend the time to do something constructive with their lives. It took two years to build that tunnel, a half a mile.

COLMES: Amazing they could build it and not be detected building the tunnel.

HANNITY: It is. It's remarkable, the level of sophistication. He said the engineers that designed that tunnel were the best. Really sophisticated.

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