Transcript for New details about gunman who attacked Navy base in Pensacola
New details emerging about the shooter in last week's deadly Navy base attack in Pensacola, Florida. ABC news has obtained a joint intelligence bulletin detailing some of what investigators have found out about the gunman since that attack and Stephanie Ramos joins us with what we have learned. Good morning to you, Stephanie. Reporter: Eva, good morning. In that joint intelligence bulletin various law enforcement agencies have detailed some of what investigators have learned about the gunman in the naval air station shooting since the attack last week. This morning, new details in the naval air station Pensacola shooting investigation. Law enforcement agencies including the FBI and dhs revealing in one report that on September 11 of this year shooter Mohammed alshamrani posted on his social media accounts the phrase, the countdown has started. Other posts included references to non-muslims as infidels and alshamrani also defending jihad. The things that he talks about as references are textbook references of people who commit terrorist acts. Reporter: Here's what investigators say they've also found in the week since the lethal attack. The shooting lasted about 15 minutes. Alshamrani firing about 180 rounds from his legally purchased handgun with an extended magazine. During the rampage, he fired at pictures of president trump and another unnamed president, and a witness claims alshamrani made comments critical of U.S. Military action overseas as he was shooting. He basically is saying the same thing that many terrorists before him have said, that the U.S. Is the enemy because they attack muslims overseas or they help other countries attack muslims overseas and that's their justification to attack us. Over ten patients confirmed. Reporter: Alshamrani opened fire last Friday in a classroom building at the naval air station killing 21-year-old airmen apprentice Cameron Walters, 19-year-old airman Mohammed haitham and 23-year-old Joshua Watson all students at the aviation school. Eight others wounded including two officers, deputies later killing alshamrani after a chase. This morning, the FBI tells ABC news the investigation remains active. Agents are working to determine still if the shooter acted alone or if anyone helped him in any way. Now, the FBI continues to work with the presumption this was a terror attack. This way law enforcement officials can use a wide range of investigative tools available only in terrorism cases. Complex case and brave Americans killed in that attack. Absolutely. Those families in mourning. Stephanie Ramos, thank you.
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