This is a rush transcript from "Special Report," March 12, 2015. This copy may not be in its final form and may be updated.
BRET BAIER, ANCHOR: The Obama administration says it is aware of the allegations that some Iraqi military units have committed atrocities similar to those by ISIS terrorists. Officials say the Iraqi government is investigating and that the U.S. has already withheld assistance to certain Iraqi units.
A counterterrorism source tells Fox News, ISIS has released a new 28-minute audio-only tape. We are told the lack of video may be a sign of increased caution. It is also being interpreted as more moderate in tone than previous messages.
Iranian-backed Iraqi troops and militia are said to be getting closer to reaching the center of Tikrit and driving ISIS terrorists out of that key Iraqi city.
Coming up this weekend, we take a closer look at the savagery that ISIS uses on its victims during a Fox News reporting special featuring freelance journalist Benjamin Hall.
(BEGIN VIDEO CLIP)
BENJAMIN HALL, JOURNALIST: They are now attacking en masse and we have decided to pull out. You know, anyone who thinks that ISIS are being pushed back or on the defensive in this whole conflict need only to come to the front line like this to realize, that in fact, much more is needed to defeat them.
We've just heard that ISIS have attacked the emplacement where we were up just an hour ago. It's right up on the front lines in Sinjar city, about 700 meters from here. Sounds as if one man has lost a leg and an arm and I'm just not sure he is going to make it.
(END VIDEO CLIP)
BAIER: Benjamin Hall joins us tonight. He is the author of the book "Inside ISIS: The Brutal Rise of a Terrorist Army". He has been on the front lines, as you can see, and has seen the ISIS tactics first hand. Benjamin -- thanks for being here.
HALL: Thank you very much -- Bret.
BAIER: For people who don't know ISIS, they only know these videos that they see that have been posted on the Internet, how would you describe it? Paint a picture of these villages in Iraq that have been overtaken?
HALL: Yes. Well, I mean if you have seen some of the videos that are out there, you haven't seen any of them yet. I mean, the truth on the ground is a lot worse than you could imagine because it is whole civilizations, whole families, whole cultures being razed to the ground.
And, as you drive through those lands as we did for this special and for the book, you start to realize the extent of it. One after the other completely abandoned; people walking around, desperately trying to find their families and with very little hope.
BAIER: And the women sold as slaves. The men, many of them killed, right?
HALL: That's right. In some cases, whole villages and whole families left without a male.
BAIER: You have video of the Peshmerga. These are the Kurdish fighters that are really on the frontlines fighting ISIS. Describe some of this fighting and, again, we have had many Kurdish leaders on this program saying they are still not getting the help that they need from the U.S.
HALL: And, if there's anyone that we should really be supporting, if there is one people -- one group of people who we need, it's the Kurds and it's amazing. Every time you go out there and I'm on the front lines, they say to me, where's the help? We desperately need it?
I, for one, have no idea why it's not coming.
BAIER: I mean they are fighting with antiquated weapons?
HALL: I mean worse than that. They are running out of bullets at the front lines. And, sometimes they have to use the five or six that they have at the time and then have to pull back and that's why no ground is being taken against ISIS.
BAIER: And ISIS obviously has all the material and equipment left by the Iraqi military, much of it U.S.
HALL: That's right and they seem to be, you know, having to supply that again and again.
BAIER: Do you sense that ISIS is going to be -- can be defeated by a relatively organized force, that they can be taken down, just seeing what you've seen on the front lines?
HALL: Well, look there are two very different battle grounds here, there's Iraq and there's Syria. In Iraq, yes, I do think there's a possibility that that change can happen and we can defeat them but not by Iranian-backed Shia militia because that feeds into the whole underlying problems. In Syria, I don't know what kind of a ground force can possibly do that and we certainly can't leave it up to the Syrians or any of the others.
BAIER: When you mention Iran, obviously, these Iranian-backed forces are trying to move into Tikrit, you sense that that would cause even more of a problem ethnically across cultures if that happens?
HALL: And it already is, you know. We're seeing sectarian violence. We are seeing some horrible videos just this morning come out of Tikrit. I mean that is Saddam's hometown and to be saved by the Shia militia who for many years have been violently killing you is just not going to work.
BAIER: What brought you there? Because obviously, it is a dangerous assignment?
HALL: Yes, six years ago, I went to cover the optimism of Iraq, the westernization, post-surge and there was a possibility there that in 2006, 2007 things were going up. I got caught up in that story, and today, I find myself reporting on something which is very pessimistic.
BAIER: What surprised you most?
HALL: It's the scale of the atrocities and the hopelessness and the lack of support that's being given to the people who are fighting, you know, for the good of the people.
BAIER: Because you talked to all of these people who have been through this, whole villages taken out and some of the families separate?
HALL: That's right. It doesn't seem like they are any closer to solving any of those stories.
BAIER: Benjamin -- thank you very much. Again, the book is "Inside ISIS". It's a great read, very detailed. And please join us tomorrow for the premiere of "Fox News Reporting : Unholy War, the March of ISIS", you can see it Friday at 10 p.m. Eastern. It will air again over the weekend.
Benjamin -- thank you.
HALL: Thank you.
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