Stephen Paddock planned to escape after the attack.
Details of Paddockâs bloody rampage emerged Wednesday as investigators struggled to pinpoint a motive in the deadliest mass shooting in modern U.S. history.
Authorities scoured the 64-year-old killerâs cell phone and electrical devices for clues as to why Paddock snapped after a fairly nondescript life with zero criminal history.
âThis individual and this attack didnât leave the sort of immediately accessible thumbprints that you find on some mass-casualty attacks,â said FBI Deputy Director Andrew McCabe.
Law enforcement officials provided a glimpse into Paddockâs final moments in his killing nest on the 32nd-floor of the Mandalay Bay Resort and Casino.
Officials said cameras placed on a food cart in the hallway and on the peephole of the hotel room door were not recording and a baby monitor camera was in the room, police said. He was likely monitoring foot traffic in the hallway.
Sheriff Joseph Lombardo did not provide details, but said officials believe Paddock planned to survive and had made plans to escape following the carnage.
Officials said Paddock purchased 33 weapons since October 2016 â most of them rifles. About two dozen weapons were found inside the room where he fired down on a crowd of 22,000.
At least 58 people were killed. More than 500 were injured â shot, hit by shrapnel or trampled by terrified concertgoers.
Paddock also fired more than 200 rounds at a security guard in the hallway before shooting himself to death just as police closed in. Miraculously, the guard survived.
Mass shooting at Mandalay Bay Hotel and Casino in Las Vegas
Paddock, a self-made millionaire and the son of a bank robber, had a prescription for the anxiety-fighting drug Valium filled just four months ago, the Las Vegas Review Journal reported.
Paddock received a doctorâs prescription for 50 tablets of 10 milligrams each, the paper said.
The recent rash of gun purchases brought Paddockâs arsenal to a total of 47 since 1982.
ATF Special Agent-in-Charge Jill Snyder said the volume of gun buys would not sound alarm bells at her agency. Only transactions where two or more handguns are sold at once appear on their radar.
âWe wouldnât get notified of the purchase of the rifles,â said Snyder during a âCBS This Morningâ appearance. âThereâs no federal law requiring that.â
A dozen of his guns were fitted with bump stocks, allowing the gunman to fire rifles almost as if they were automatic â unleashing massive amounts of mayhem in a short time.
The rifle magazines used by Paddock held anywhere from 60 to 100 bullets each, Snyder told CBS News, cutting back on his need to keep reloading.
Officials also revealed Wednesday that Paddock had rented a room through Airbnb at the Ogden hotel in downtown Las Vegas during another music festival a week before the massacre.
Authorities were also investigating whether Paddock practiced at any of the gun ranges on or near the Vegas Strip.Â