LAS VEGAS • Federal Bureau of Investigation agents were set to begin questioning the Filipino Australian girlfriend of the Las Vegas gunman following her return to the United States from Asia, in their search for answers into what sparked the deadliest mass shooting in modern US history.

Investigators hoped Ms Marilou Danley, 62, would be able to provide glimpses into the mindset of the killer, 64-year-old Stephen Paddock, whose intricate planning turned a hotel suite into an armed fortress with hidden cameras.

So far, few clues have emerged to help investigators understand the evil he rained down on an outdoor country music concert on the famed Las Vegas Strip - leaving at least 58 dead and once again bringing calls for greater gun controls to the centre of political debate.

Against a backdrop of anguish and anger over Sunday's massacre, US President Donald Trump planned to travel to Las Vegas yesterday to address law enforcement officials and survivors.

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