Transcript for Investigators seek answers from Las Vegas gunman's girlfriend
development, the gunman's girlfriend, she is back in the U.S. Tonight, being questioned by the FBI. Her brother telling ABC news that she assured her family she has a, quote, clean conscience. But tonight, she remains a person of interest, as they now ask, how the gunman assembled such an arsenal without anyone noticing. Here's ABC's chief investigative correspondent Brian Ross. Reporter: Tonight, just 12 hours after she arrived on a flight from the Philippines, the shooter's long-time girlfriend, Marilou Danley told the FBI, according to law enforcement officials, that she had no knowledge of his plans or his purchase of so many guns. Her lawyer read her statement after the FBI session ended. He never said anything to me or took any action that I was aware of that I understood in any way to be a warning that something horrible like this was going to happen. Reporter: Danley had been paddock's live-in girlfriend for at least three years. He met her when she was a casino hostess. They gambled together, playing video poker and the slots. Investigators want to know if he went along when she traveled to dubai, where she posted this smiling photo. According to her sisters in Australia, who wanted their faces blurred, no one knows more about paddock. No one can put the puzzles together. No one. Except Marilou. Reporter: The sisters said paddock who sent her to the Philippines just two weeks before the shooting. He sent her away. So that he can plan what he is planning without interruptions. Reporter: Authorities now are putting together a psychological profile of the shooter. A 64-year-old one-time accountant and irs agent, who claimed to be a multimillionaire. But investigators say a picture is emerging of a man "Descending into madness," losing weight, diminished physical appearance, what are described as "Crazy eyes." Coupled with easy access to the powerful weapons he began to accumulate at least a year ago, a deadly combination. Brian Ross with us live from New York tonight. And Brian, we heard your report there, the shooter's girlfriend spent hours today talking to the FBI. But she is denying knowing anything about this plot? Reporter: Yes, David. Officials say she claims she had no idea about the dozens of guns her boyfriend bought over the last year, and as you said, her brother tells ABC news, she told her family she has a clean conscience, David. Brian Ross and your team. We thank you again tonight.
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