A federal law enforcement official earlier said two rifles were outfitted with scopes and set up on tripods in front of two big windows. Another official said that among the weapons were AR-15-style assault rifles. Both officials spoke on the condition of anonymity because they were not authorized to divulge details of the investigation.
Sheriff Lombardo said that Mr. Paddock brought at least 10 suitcases into his hotel room over a period of time.
The sheriff said that Mr. Paddock fired through his hotel room door at security guards, striking one in the leg. The guard is still alive, he said. SWAT officers went in after the guard was shot.
In addition to the weapons at the hotel, the sheriff said the police retrieved 19 firearms, as well as explosives, several thousand rounds of ammunition and âelectronic devicesâ from Mr. Paddockâs home in Mesquite, Nev.
Paddock raised no suspicions at store where he bought several firearms.
The investigation into Mr. Paddockâs gun arsenal led investigators to New Frontier Armory, a large North Las Vegas dealer, distributor and manufacturer of firearms.
David M. Famiglietti, the companyâs president, issued a statement on Tuesday confirming that Mr. Paddock purchased âseveralâ rifles and shotguns from the business last spring â all at the same time. Itâs not uncommon for customers to do this to save money on background check fees, Mr. Famiglietti said.
âThe firearms he purchased did not leave our store capable of what weâve seen and heard in the video without modification,â he said. âThey were not fully automatic firearms, nor were they modified in any way â legally or illegally â when they were purchased from us.â
Mr. Famiglietti said that nothing about Mr. Paddock raised red flags with the storeâs sales clerk. On the contrary, according to Mr. Famiglietti, Mr. Paddock seemed to be interested in competitive shooting, asking the clerk a lot of questions about three-gun shooting matches â an increasingly popular sport in which players use a rifle, a shotgun and a pistol.
âHe just seemed like a normal guy,â said Mr. Famiglietti, whose store has been the target of hate mail, threatening phone calls and fake reviews since the shooting. âWe obviously did not sell him these firearms with the intent that he would use them to hurt anyone in any way.â
On Monday, a Mesquite, Nev., gun dealer, Guns & Guitars, acknowledged having sold two rifles and a handgun to Mr. Paddock. Like the purchases at Frontier, those were cleared by state and federal background checks.
The gunman was ânot an avid gun guy at all,â said one of his brothers.
Mr. Paddock, 64, was described as a high-flying gambler who lived in a quiet retirement community and played golf. Officials said he had no significant criminal history and drew little attention to himself.
Investigators are trying to piece together his financial history to search for clues that could help determine what set him off.
Mr. Paddock worked for the federal government for roughly 10 years, from 1975 to 1985, a spokeswoman for the federal Office of Personnel Management confirmed on Tuesday. Investigators unearthed multiple job applications, with Mr. Paddockâs fingerprints on file, as part of records reflecting his employment as a letter carrier for the Postal Service; as an I.R.S. agent; and as an auditor of defense contracts.
Details about Mr. Paddockâs later career and livelihood were sparse, aside from observations by neighbors and family members that he routinely gambled large amounts of money. âHe was a wealthy guy, playing video poker, who went cruising all the time and lived in a hotel room,â a brother, Eric Paddock, said.
Mr. Paddock and his three brothers were raised by their mother, who told the children their father had died when in fact he was in prison, Eric Paddock said. Mr. Paddockâs father was convicted in 1961 of committing a series of bank robberies and was sentenced to 20 years in prison. He escaped from La Tuna federal prison in Texas in 1968 and became a used-car dealer and bingo parlor operator in Oregon.
In an interview with CBS, Eric Paddock said that his brother Stephen was ânot an avid gun guy at all.â
âThe fact that he had those kind of weapons is just â where the hell did he get automatic weapons?â he asked.
âIâve never been that scared in my life,â said one witness.
The police estimated that when the shooting began, there were 22,000 people at the Harvest Festival, listening to Jason Aldean, the final act of the three-day event.
Video of the shooting captured nine seconds of continuous, rapid fire, followed by 37 seconds of silence from the weapon and panicked screaming from the crowd. Gunfire then erupted again and again in extended bursts. Some concertgoers thought the noise was fireworks, but as it became clear what was happening, people fled, many of them unsure where the shots were coming from, or where they should go.
âEveryone was running, you could see people getting shot,â said Gail Davis, one of the witnesses. âIâve never been that scared in my life,â she added. âTo have this happen, I canât wrap my mind around it.â
Video from the shooting showed Mr. Aldean running off the stage as the gunfire erupted.
Within minutes, a police officer on the scene radioed âto report cases of gunshot wounds âto the chest, legs, terminal arteries at the medical tent.â
A few minutes later, an officer said, âWeâre making tourniquets out of blankets, but Iâm running out of blankets here.â
Patients surged into Sunrise Hospital and Medical Center, where at least 124 âmet the criteria for trauma activation,â said Dr. Jeff Murawsky, the hospitalâs chief medical officer. They included patients with single and multiple gunshot wounds to the head, face, chest, body, arms and, in one case, a finger.