Major change to timeline of events in Las Vegas shooting

Stephen Paddock before the shooting

REUTERS 'TURN IT DOWN Paddock made noise complaints

The 64-year-old Stephen Paddock opened fire from his 32-floor hotel room on the crowd of almost 20,000 people at the country music festival on the Las Vegas Strip on previous Sunday night, leaving 58 people dead and more than 500 people injured. The 64-year-old Paddock killed himself as authorities closed in.

The latest update still indicates Paddock shot Campos when the security guard reported to the floor in response to a report of an open door.

Hundreds of people attend a vigil marking the one-week anniversary of the October 1 mass shooting in Las Vegas, Nevada.

Police were not in a hurry to enter Paddock's suite because the security guard's arrival had halted the shooting, police implied in previously describing the timeline.

The encounter with Campos on the hotel's 32nd floor happened at 9:59 PM local time, six minutes before a gunman began firing into the crowd, Sheriff Joseph Lombardo revealed at a Monday afternoon news conference.

A handful of quick-thinking Las Vegas police officers may have prevented a thousand deaths after they stormed a hotel and killed the lone shooter, the sheriff of America's gambling hub who had visited Mumbai to study the 26/11 terror attack has said.

The officers say Paddock screwed shut a stairwell door to slow them down. Authorities discovered he had filled his room with 23 guns, aided with scopes and "bump-stocks," which allow rifles to fire faster and essentially convert semi-automatic weapons into something more akin to automatic weapons.

"Today, in our investigation, we don't have any of that uncovered", McMahill said.

They said a piece of paper found in the shooter's hotel room had calculations scrawled across it determining ballistic trajectories that would help the gunman maximise his death toll.

The FBI says it has processed the objects and belongings left behind the night of the shooting.

Police state that Paddock fired 200 rounds into the hallway.

In addition, Lombardo said Paddock's motives were still unclear and there was no evidence that he had been motivated by any ideology.

Authorities are planning to put up billboards in Las Vegas to seek more tips as they investigate the shooting.

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