This is a partial transcript from "On the Record," April 16, 2007, that has been edited for clarity.

GRETA VAN SUSTEREN, HOST: The gunman at Virginia Tech was armed with a nine millimeter pistol and a .22 caliber handgun, according to reports. Mike Haag is a firearms expert. He joins from us New Mexico.

Mike, tell us about the weapons that this man, at least is being reported, that he used to kill the 32 people, here on this campus?

MIKE HAAG, FIREARMS EXPERT: Well, Greta, while we don't know exactly what firearms makes and models may have been involved in this particular case, I brought with me a few different types of firearms as demonstrative aids. For example, this is nine millimeter, automatic handgun that operates like many of the semiautomatic handguns that are on the market today.

VAN SUSTEREN: Is that to mean — when you see the number of people who are killed, here, 32. Two, of course, were in a one place and then 30 at the classroom building, does it surprise you using that particular weapon that you'd be able to accomplish that in this amount of time? And is it — is that — is that weapon — you know — does it have that much firepower — that much — I mean, I suppose he had lot of ammunition, but is that the weapon of choice?

HAAG: Well, I'd step back and say, first of all, as someone who works with firearms on a daily basis in and out, it's simply a machine, it's simply a tool, it has no bias, it has no objective, it's only as good as or as bad as the individual user of the firearm. So, the fact this many people are skilled is certainly odd. The fact that the doors were chained gives certainly gives some logical reason for why we have so many people who are shot and wounded in this particular case.

VAN SUSTEREN: All right. That's a nine millimeter, what about a .22 caliber?

HAAG: Well, there are different kinds of .22 calibers. There are even nine millimeter caliber revolvers. I brought with me a 22 caliber, semiautomatic pistol, also. But because we don't know yet whether it's a revolver or semiautomatic pistol, I can't give you anymore information about that.

Again, this is an example of a 22 caliber pistol, the color the shape, the size could vary greatly depending on what they're finding at the crime scene. And given so many people were either killed or wounded in this case, I'm not surprised that this information hasn't come out yet. I would expect the police department to be keeping this information very tight-lipped, if you will, at this point in the investigation. They've got a lot of work to do and they're going to be out there for probably days, given how many shots were fired and the number of locations.

VAN SUSTEREN: Why would they keep that information tight-lipped at this point? I mean, if the killer, at least, we assume that this is alone killer, I mean, there's no suggestion there's anybody out there. And I would assume that they would want to match, like, shell casings from one crime scene with the other to try to identify the weapon and identify that it was, indeed, one person. I mean, why keep that quiet right now?

HAAG: That would be quiet practice. You don't want a bunch of rumors getting out before you can get an official statement out of what is true and correct. That happens in so many cases where you're got misinformation that's either leaked on accident or on purpose. It's better just to wait, take your time, as far as the physical evidence goes, and logically systematically and cleanly go through it. I can guarantee you there's a firearms examiner somewhere out the world who is waiting for this stuff to arrive so they begin their benchmark on it.

VAN SUSTEREN: And I assume that it's relatively easy to make this match up, this ballistics comparison to the two crime scenes?

HAAG: No, you never make that assumption. The identification of bullets or cartridge casings to a particular firearm is not always very easy. It's not always very hard. It really depends on the particular firearm that is involved and how it was machined to create the microscopic markings that are then transferred from the gun, the tool, onto the bullets or cartridge casings. So, there are lots of different factors.

There's no way to predict whether it's going to be an easy identification or hard one. Until that examiner gets it on their microscope and starts to do their examination.

VAN SUSTEREN: Mike, thank you.

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