Investigators just changed a key part of the timeline in the Las Vegas shooting

Las Vegas shootingDavid Becker/Getty ImagesPolice tape blocks an entrance at the Mandalay Bay Resort & Casino on October 4, 2017 in Las Vegas, Nevada.

Police investigating the Las Vegas shooting have updated their timeline of the events leading up to the massacre that unfolded on October 1.

Investigators in Las Vegas now believe a security guard who was the first to encounter gunman Stephen Paddock did so at 9:59 p.m. local time — six minutes before Paddock began firing on the crowd of 22,000 concertgoers at the Route 91 country music festival, killing 58 people and injuring hundreds more.

The security guard, Jesus Campos, was shot in the leg by some of the more than 200 rounds that Paddock fired into the hallway outside of his 32nd-floor suite at the Mandalay Bay Resort & Casino. “Immediately upon being injured, he notified security,” Sheriff Joseph Lombardo said of the hotel guard at a Monday evening briefing.

Police clarified that Campos had been responding to an alarm associated with an open door on the 32nd floor that was unrelated to Paddock’s room. The guard then heard drilling coming from where the gunman was staying. Investigators said Paddock may have been drilling to set up another camera. He had already placed two cameras in the hallway and had others in his room.

A maintenance worker arrived to the 32nd floor shortly after Campos was injured, but Campos “prevented him from receiving any injuries,” Lombardo said.

Paddock began shooting at the festival crowd at 10:05 p.m., but Lombardo said that he is not assuming the encounter with Campos made Paddock — who had meticulously planned his attack — change his timeline.

Police first encountered Campos when they got to the 32nd floor at 10:17 p.m. and met him in the corridor.

Lombardo also revisited his previous comments around a potential escape plan Paddock may have had:

“That’s been a matter of discussion, whether what I said was accurate or not. And what I am comfortable with saying is what I believe. The suspect, we know that he attempted to shoot at the fuel tanks, we know that he had some personal protection equipment in the room, we know that the car that was found in the parking garage still, contained binary explosives. So I would be comfortable in saying, which I believe, dependent on the splash he made during the shooting would have enabled the first responders to be directing their attentions to other locations which would enable Mr. Paddock to just leave the hotel. We do not know whether he had planned to cause additional harm outside of what occurred at Mandalay Bay,” Lombardo said.

The investigation into the shooting, now considered the deadliest in modern US history, is ongoing. Law-enforcement officials have interviewed Paddock’s family members and his girlfriend, Marilou Danley, who Paddock sent out of the country ahead of the attack.

Police say that, so far, they believe Paddock acted alone.

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