Transcript for FBI looking into whether Pensacola naval base suspect watched mass-shooting videos
I'm Tom llamas. We begin tonight with the new details in the deadly shooting at the Pensacola naval base. With authorities investigating it as a possible act of terror. The FBI tonight trying to determine whether the 21-year-old Saudi national acted alone when he opened fire inside a military building at the base where he was training. Authorities combing through his electronic footprint, probing reports he watched mass shooting videos with friends to pump himself up. At the same time, the three victims killed in the attack have now been identified. With the gunman's Saudi classmates on the base reportedly cooperating. Stephanie Ramos leads us off from Pensacola. Reporter: Tonight, the deadly attack at the naval air station in Pensacola now a terror investigation. Hundreds of federal agents working around the clock to determine if gunman Mohammed alshamrani had help in carrying out his shooting spree. Our main goal right now is to confirm whether he acted alone, or was he a part of a larger network? Reporter: Authorities say the gunman's Saudi classmates are being kept on the base and cooperating with questioning. Alshamrani, a member of the Saudi air force, in Pensacola as part of a pilot training program. Military bases now on alert, but authorities emphasizing there's no known danger. I know that the community is safe and there is not any immediate, direct threat of any additional terrorist acts at this time. Reporter: Officials tracing the gunman's footsteps, claiming he and several classmates made a recent sightseeing trip to New York City. Sources now telling ABC news they're investigating classmates' claims that alshamrani watched videos of mass shootings in front of friends at his home just days before the carnage. They believe it served as a way of psyching himself up. Members of the FBI's joint terrorism task force are working tirelessly to discern, if any, possible ideology that may have been a factor in this attack. Reporter: The FBI now pouring through surveillance images and cell phone recorded from a bystander taken directly after his deadly rampage. It was a 45 Glock 9 millimeter. He did purchase it legally and lawfully. Reporter: Tonight, a solemn procession mourning the loss of three sailors. 23-year-old Joshua Watson, who aspired to be a jet pilot. Sameh haitham, whose father called an exceptional kid. And 21-year-old Cameron Walters, a Navy aviation student. The two officers wounded after heroically confronting the gunman are recovering. The deputies that went in and neutralized this evil, if you will, and were able to save countless lives. Stephanie, we just heard in your story that the gunman legally purchased his firearm. He was not a citizen of the United States. How did he obtain a firearm here? Reporter: Tom, normally a non-u.s. Citizen cannot legally obtain a gun. However, there is an exception under federal law that allows an official representative from a friendly foreign government to obtain one. Tom? Stephanie, thank you. Next to the winter whiplash. As a major storm sweeps east
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