The rapid rat-tat-tat-tat of gunfire that engulfed a country music festival in Las Vegas Sunday night, killing nearly 60 people and wounding hundreds more, left little doubt that the shooter was using an automatic weapon.
Authorities confirmed Monday that 23 firearms, some equipped with scopes, had been recovered from the 32nd-floor Mandalay Bay hotel room where the shooter, Stephen Paddock, had been staying.
On Tuesday, Clark County Sheriff Joseph Lombardo said he couldn't say whether any of the weapons were automatic or not, but confirmed a device known as a "bump stock" was used by the gunman.
"We are aware of a device, called a bump stock, and that enables an individual to speed up the discharge of ammunition," Lombardo said.
In total, 12 guns found in the hotel suite were equipped with bump stock fire devices, said ATF Special Agent in Charge of the San Francisco office, Jill Snyder, making them capable of firing like an automatic weapon — legally.
Federal law makes it difficult and expensive for the average person to get their hands on a fully automatic weapon. But gun control advocates told BuzzFeed News that Nevada law makes it easy and relatively cheap for anyone to purchase a small device that makes an assault rifle fire like a machine gun.
Federal regulation might have put automatic weapons out of the reach of most buyers, but with devices such as bump stocks or trigger cranks, it doesn't matter, effectively creating a "loop hole" for anyone looking to modify their weapons.
Now, as police continue their investigation into Paddock, discussion has already begun on what role, if any, the state's gun laws may have played in what has become the largest mass shooting in recent US history.
"People talk about machine guns being banned, but they're not," Laura Cutilletta, legal director for the Law Center to Prevent Gun Violence, told BuzzFeed News. Though some states have banned their sale altogether, she added, Nevada has not.
Under federal law, Cutilletta said, only automatic weapons made before May 19, 1986, are allowed to be sold, and all sales must be approved and registered with the Bureau of Alcohol, Tobacco, and Firearms, or ATF.
The federal restrictions have in effect priced these firearms out of the US market, putting them out of reach of most gun owners. Still, according to a 2017 ATF report, there are currently 630,019 automatic weapons registered with the federal agency, including 11,752 registered in the state of Nevada.
And despite federal limits, it is relatively easy for someone in Nevada to make a semi-automatic rifle fire like an automatic weapon.
That's because the state has no restrictions on the sale of "trigger cranks" or "bump stock" devices, a relatively simple modification that allows the shooter to pull the trigger of an assault-rifle-style weapon much more rapidly, replicating the damage of an automatic weapon.
Photos leaked to Fox affiliate Boston 25, seem to show that at least one of the weapons was equipped with a bump stock, which can speed up the weapon to shoot several rounds per second.
Las Vegas Metropolitan Police Department Undersheriff Kevin McMahill confirmed Tuesday evening the leaked photos were real pictures of the hotel suite. An internal investigation into the leaking of the images is currently underway, he added.
All weapons have been taken to the FBI's crime lab in Virginia to be inspected, Lombardo said, and to determine if any were automatic, and what modifications were made.
Asked about the weapons officers faced by officers as they tried to reach Paddock in his hotel suite, Lombardo said he was concerned.
"The world has changed," Lombardo said. "Who would have imagined this situation?"
Gun control advocates have focused much of their attention on the outright ban of assault weapons, but the Assault Weapons Ban in 2013, introduced shortly after the Sandy Hook shooting that left 20 children and six adults dead, included a ban on the devices as well.
The bill was defeated.
"Somebody punches out two big windows and kills all those people and wounds all those people, and turns semi-automatic weapons into automatic weapons, which are—from the National Firearms Act—have been long prohibited, and we ought to do something about it," California Sen. Dianne Feinstein told reporters Tuesday. "We ought to take some steps because it just gets worse and worse."
The devices are banned in some states, including California. They are legal in Nevada, and are available for an AR-15-style rifle online at a cost of anywhere between $250 and $350.
Feinstein said she is looking at a way to address the issue, once more, through legislation.
"I think that's something that will need to be addressed, whether or not it turns out that's what was used," Cutilletta said. "The fact that's available and not addressed through legislation is a real loophole."
"If you're effectively making something a machine gun, you know, I think it's safe to say it should be regulated like one," she added.
Paddock's arsenal of weapons also would not have been difficult to compile in Nevada, where there is no permit required of people purchasing firearms and no limit to how many weapons can be purchased at one time.
Though background checks are conducted whenever someone purchases a weapon from a licensed dealer, advocates on both sides of the gun debate argue that such checks would not have stopped Sunday's massacre.
"The guy doesn't have a criminal history," Don Turner, president of the Nevada Firearms Association, a gun-rights advocacy group, told BuzzFeed News. "Background checks would not have stopped this."
Guns & Guitars, a gun shop in Mesquite, Nevada, where the shooter purchased more than one weapon, confirmed that Paddock passed all the required background checks.
"He never gave any indication or reason to believe he was unstable or unfit at any time," Christopher Sullivan, the shop's manager, told BuzzFeed News.
Turner, who said his organization favors mandatory sentencing for people in possession of illegal guns rather than tougher restrictions on purchases, described Nevada's approach to gun regulation as "libertarian."
He also argued that no amount of legislation could prevent violence completely. "When a person has this much evil intent in their heart, the gun doesn't have to be, it's just a tool," he said.
But Nevada's gun culture is not easy to miss. Advertisements across the state tout desert outings where people can shoot automatic weapons themselves. The right to keep and bear arms is reiterated in the state's constitution, and the state does not require permits to purchase rifles or handguns, or mandate registration of firearms.
Nevada is also an "open carry" state, which means gun owners can visibly carry firearms on their person without a permit. A permit is required to carry concealed weapons, but Nevada is considered a "shall issue" state, which means that sheriffs' departments issuing concealed weapon permits must approve applications as long as all the requirements are met.
In Clark County, which is home to Las Vegas, residents are required to pass a background check, be 21 years old, and complete a course in order to obtain a concealed carry permit. Unlike in some states, applicants are not asked to explain why they need to carry a concealed weapon.
According to the Law Center to Prevent Gun Violence, Nevada requires people under domestic violence protective orders to surrender their guns to law enforcement. Mental health records are submitted to the National Instant Criminal Background Check System.
Turner said he worries Sunday's shooting in Las Vegas may spark new calls for gun control legislation in Nevada. "There will be a lot of discussion, a lot of fundraising, a lot of emotionalism," he said. "They'll focus on symbolic things."
He pointed to a state law, passed last year, that would have made background checks mandatory during private gun sales. The law never took effect, after Nevada Attorney General Adam Paul Laxalt, who spoke at an NRA forum in April, issued an opinion that the state could not enforce the measure, leaving the legislation in limbo.
Emma Loop contributed to this report.