Transcript for Aaron Alexis Heard Noises in Navy Barracks Linen Closet
latest on the navy yard shooting. The warning signs were there. Abc news has learned that shooter aaron alexis was kicked out of the navy housing just weeks before his rampage because he was raving about voices in his head. Abc's pierre thomas is tracking the investigation in washington. Good morning, pierre. Reporter: Good morning, george. Today, even more warning signs missed. And disturbing new details about how the suspect had free reign to kill those victims. Law enforcement sources tell abc news, aaron alexis abruptly left a newport, rhode island, navy barracks, after complaining that noises were coming out of his linen closet. Newport naval station police were warned that alexis was hearing voices and claiming he was under surveillance by figures. But navy did not pass that up the chain of command. There should have been a mental health assessment done, in order to determine the severity of these hallucinations. Reporter: Alexis' mental state appeared to be deteriorating. Six days before alexis came to washington, he went to a temple, campaigning to monks, that he was hearing voices. He said he didn't sleep. Reporter: The fbi is investigating whether alexis targeted specific co-workers. And new fbi director, james comey, told reporters, disturbing new details thursday. He says alexis was working on a computer server program in navy yard building 197, which allowed him to enter and move about the facility freely. And we learned, he sawed off his shotgun with a hacksaw, bought at a home depot, and hid it in a bag. Alexis appeared to be hunting people, in a random way without pattern. So much heartache. On sunday, president obama plans to attend the service honoring the fallen. We continue to think about them here. Thank you.
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