In the 72-minute shooting, 58 people were killed and 527 were injured as they attended a Route 91 Harvest Festival along the Las Vegas Strip. But the guard managed to direct police to the exact location of Paddock's suite and even provided a hotel key to officers looking to clear rooms on the 32nd floor before they insisted he get medical attention.
Paddock was able to fire on the crowd for 10 minutes before officers arrived, engaged the suspect and were able to pry open the door. Authorities do not yet know what made him stop shooting, Lombardo said.
"He was injured prior to the mass volley of shooting", the sheriff said during a Monday afternoon news conference.
Charles "Sid" Heal, a retired Los Angeles County sheriff's commander and tactical expert, said the new timeline "changes the whole perspective of the shooting".
"It was a tragedy of unimaginable proportions", Pence said as he addressed almost 300 people at Las Vegas City Hall Saturday afternoon. "So he had had that written down and figured out so he would know where to shoot to hit his targets from there". Investigators found more than 40 firearms in Paddock's hotel room and at his residence in Mesquite, Nevada.
Paddock worked for a time as an Internal Revenue Service agent, then began to invest in real estate, CNN reported.
"Like everyone, I'm struggling to understand what happened that night", Aldean said.
The Las Vegas gunman, who killed concertgoers in the city last weekend leaving 59 people dead and more than 500 people wounded, had first opened fire on a security guard.
Sheriff Lombardo concluded the briefing by confirming that authorities are still in contact with Paddock's girlfriend Marilou Danley who was out of the country in the Philippines prior to the mass shooting.
"This individual purposely hid his actions leading up to this event, and it is hard for us to find the answers", said Lombardo, who said he was frustrated with the speed of the investigation.
Lombardo said Paddock was drilling a wall near a doorway but didn't finish.
Paddock had a document in the room with him that contained numbers, Lombardo said, adding he could not immediately say what goal the figures served.
The move made her "grateful, but anxious", thinking that Paddock was breaking up with her, she said in her statement.
Eric Paddock said that when Stephen Paddock's body is released, he wants to have his remains cremated and sent to their 89-year-old mother, who also lives in Orange County.
Investigators have chased 1,000 leads and examined Paddock's politics, finances, any possible radicalization and his social behavior - typical investigative avenues that have helped uncover the motive in past shootings.