Transcript for Probe continues into deadly shootings at Pensacola naval base
Next, we have new reporting tonight in that fast-moving investigation of the deadly rampage at the naval base in Pensacola. Three people were killed, eight injured at that training facility on Friday. The suspect, an officer in the Saudi royal air force, and tonight, investigators are now retracing his final days here in the U.S., including a trip to New York City to see the Rockefeller Christmas tree. And news he bought his gun right here in the U.S. ABC's Stephanie Ramos in Pensacola tonight. Reporter: Tonight, new clues about the days leading up to that deadly rampage in Pensacola, as the FBI investigates whether the attack by a Saudi air force lieutenant was a terrorist act. Our main goal right now is to confirm whether he acted alone or was he a part of a larger network? Reporter: Investigators believe Mohammed alshamrani posted an anti-american rant on Twitter shortly before the attack, quoting Osama bin laden. This guy was somebody who, you know, just had a deep-seeded hatred for the United States. Reporter: Sources tell ABC news alshamrani, who was training at the naval air station, filed a complaint in April against an instructor who he said mocked his mustache. Investigator now retracing his steps in the days before the attack. Learning he took a sightseeing trip to New York City, sources say it included a visit to Rockefeller center and the 9/11 memorial. ABC news has learned back in Pensacola, alshamrani showed friends videos of mass shootings. Later, opening fire onbase, killing Cameron waters, Mohammed haitham, and Joshua Kaleb Watson. Watson's family says the 23-year-old had a sense of duty, even at the end. With his last breath, really. He summoned all of his courage and gave a report, a description of the shooter and where he believed his location was. Reporter: The shooter was able to legally purchase the gun, because he was considered to be an official representative for an ally country, Saudi Arabia. However, personal weapons are not allowed on the base, but for this shooter, because he was also a student, he would not have been searched because he had a clearance to be here. David? All right, Stephanie Ramos, thank you. Next, the supreme court and
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