Transcript for Investigators continue to press the Las Vegas gunman's girlfriend for more details
New details about last week's mass shooting in las Vegas as we learn more about how the gunman got that arsenal into his he tell room. His girlfriend and brother are facing new scrutiny. Brian Ross with the latest. Reporter: As the FBI continues to press the shooter's longtime girlfriend for more detail she's been placed on a U.S. Government travel watch list as a key witness so the authorities will be notified if she tries to board a flight or leave the country. According to federal law enforcement authorities, Marilou Danley has been designated a selectee by the TSA. Based on her potential importance to investigators. She has denied knowing what her live-in boyfriend of three years was up to in the house they shared but one senior law enforcement official told ABC news they want to make sure Danley, an Australian citizen doesn't suddenly decide to leave the country. Authorities also say they are keeping a close eye on paddock's brother Eric who is now in las Vegas. He too has said he had no idea what his brother was planning. We're still just completely befuddled. Reporter: He reportedly cannot find a funeral home to deal with his brother's body. More than a week after the shooting, investigators still have many questions for the mandalay bay hotel. Authorities tell ABC news that paddock as a high roller was allowed use of the service elevators and he used them to bring his cases of weapons to his 32nd floor suite avoiding the security checks in place in the front lobby and questions remain about whether the hotel failed to act quickly enough after a hotel security guard called in to say he had been shot in the hallway through the door. Some six minutes before the concert rampage began. In those six minutes you may have been able to create a disruption of some sort that would have kept him from doing what he ultimately did. Reporter: The owner of the mandalay bay bay mgm would not answer any of her questions citing the ongoing investigation. And behind the scenes the FBI and the Las Vegas sheriff are apparently not getting along all that well with some agents complaining the sheriff has put obstacles in the way of their investigation, no comment, George, this morning from the FBI or the sheriff's office. A lot of questions left to answer. Thanks very much.
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