Mandalay Bay hotel staff did not notify Las Vegas police about a shooting in a hallway until after Stephen Paddock opened fire on the crowd outside at a country music festival, a federal official said.

Police have made a significant change to the timeline of the Las Vegas mass shooting, saying the gunman shot a hotel security guard before he opened fire on concert-goers.

Police have made a significant change to the timeline of the Las Vegas mass shooting, saying the gunman shot a hotel security guard before he opened fire on concertgoers.

Police investigating the Las Vegas mass shooting have said they are still no closer to working out what drove Stephen Paddock to commit mass murder.

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