Transcript for Photojournalist reveals graphic images of torture and execution by Iraqi troops

proper procedures. Alex, thank you An ABC news investigation. Where cameras rarely go. A journalist embedded with a team the U.S. Has supported. An ally of ISIS. That journalist soon became troubled the images he was capturing. Saying he was witnesses brazen torture. ABC's Brian Ross with the troubling images tonight. Reporter: These dramatic battlefield pictures were made by an Iraqi photojournalist, Ali arkady, expecting to document the heroics of Iraqi soldiers, working with the U.S. Against ISIS. They are against ISIS and they're very strong. Reporter: But arkady says he soon came to learn the soldiers he was embedded with for months, from what's called the emergency response division, were no heroes. And tonight, he is revealing the graphic images, licensed by ABC news, that he captured of these important U.S. Allies carrying out the torture and murder of civilians, only some of which can be broadcast. This is happening all the time? This is happening all the time. Reporter: This man, he says, was a sheep herder, whose teenage sons were suspected of working for ISIS. There's not even a pretext here of torture in the name of obtaining intelligence. This is just torture for fun. Reporter: Sadistic? Sadistic. Reporter: In a remarkable phone call with us, the unit captain, OMAR Nazar, admitted the video was real and said he was proud of what was on the tape. "I'm already a star and Ali would make me a bigger star by doing this." The soldiers were so proud of what they were doing they even sent arkady horrific phone videos they shot themselves, the victims they tortured and murdered. I don't even have words for it. Reporter: That's a murder, isn't it? That's a murder. Reporter: In a statement, the American embassy in Baghdad told ABC news the U.S. "Has not provided military aid, arms or assistance" to the unit. Yet, a senior U.S. Military official in Iraq was full of praise for the unit. And it has been really a fruitful partnership in all regards. You heard the leader of that unit saying he's proud of what was on that video. This photojournalist has put himself at risk by being the whistleblow zmrer he has fled Iraq and he's in hiding after receiving death threats from the very soldiers who thought he would keep their secrets and he

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