Transcript for A man opened fire outside a courthouse in Dallas before being shot and killed
And we begin tonight with the deadly shootout unfolding in broad daylight outside a federal courthouse in Dallas. A masked gunman armed with a rifle firing into the building. Heavily armed police swarming the scene today, taking him down in the parking lot. The gunman in tactical gear, wearing body armor. Federal authorities say he had more than five 30-round magazines on him. Witnesses watching the scene unfold. And late today, police re1r50e8ing new details about the suspect. ABC's Marcus Moore is in Dallas, leading us off. Shots fired, shots fired! We got S.W.A.T. Coming through. . Reporter: Tonight, a masked gunman in tactical gear firing on a Dallas federal courthouse. Just before 9:00 this morning. One person seen just to the right of the suspect taking cover just feet away. We were all in a room together in a meeting when we heard the shots. Maybe 10, 15 shots, all of this rapid. People just started running out of the building. Reporter: A photographer with "The Dallas morning news" capturing this image from just feet away. The suspect identified at 22-year-old Brian Isaac Clyde, runs to a parking lot across the street. He is shot and killed. The bomb squad conducting a controlled explosion. We were on the scene just a block away and could hear the sound. And you just heard them detonating the -- an object where the suspect vehicle was found here downtown. Multiple FBI agents raiding a ft. Worth apartment where neighbors told our Dallas station the suspect had been living. Tonight, the U.S. Army telling ABC news private first class Clyde served as an infantryman from August 2015 to February 2017. Authorities saying tonight there is no indication of other shooters or threats to the community. But for the actions of the federal protective service officers, this likely would have been a very deadly incident. And Marcus Moore with us live tonight from Dallas. And Marcus, just incredible that no one was seriously hurt in this, and authorities are telling you they are working to determine a motive? Reporter: David, authorities tell me they have more than 200 FBI agents and partners fanned out across the state as they try to connect the dots here, and they are tracing the suspect's weapon as well as interviewing those who knew him, trying to figure out a motive for this shooting. David? Marcus Moore, thank you. We are also following
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