Sunday’s horrific mass shooting in Las Vegas once again shines a light on a nation awash in guns, with relatively few restrictions on their purchase or possession.

In Nevada, like in most states, it’s legal to openly carry long guns, like rifles and shotguns. No permit is required for this sort of display. That means people are allowed to walk down the Las Vegas Strip with a military-style rifle slung over their shoulder, although casinos and other private businesses can bar those individuals from their premises.

It’s also legal in Nevada to own a fully automatic firearm, such as a machine gun, though federal regulations require owners to pay a $200 fee and submit to an extensive federal background check and fingerprinting, which can take up to a year to complete. This weaponry is regulated under the National Firearms Act. Some states have laws specifically restricting machine guns, but most don’t.

Because of the rarity of these weapons, however, fully automatic firearms can be incredibly expensive ― usually between $20,000 and $30,000, said Benjamin Bunker, a Las Vegas attorney who specializes in firearms-related matters.

“If he was gonna buy a full-auto machine gun, he would’ve found a dealer online selling it, they would have entered into a purchase agreement, he’d pay the guy, the guy would then transfer the full-auto machine gun to a dealer, and then the dealer holds on to that gun until the [Bureau of Alcohol, Tobacco, Firearms and Explosives] gives him the green light,” said Bunker.

There are plenty of firearms on the black market. But illegal full-automatic machine guns are a top priority for ATF, and are harder to find, said Bunker.

That said, Nevada does not specifically restrict open carrying of machine guns.

“Nevada doesn’t make any distinction, semi-auto versus full auto,” said Bunker.

Authorities have not yet publicly identified any weapons the gunman used on Sunday, but confirmed that the shooter rained down fully automatic gunfire on a crowd of concertgoers, killing at least 58 people and injuring more than 500 from his perch on the 32nd floor of the Mandalay Bay casino. Las Vegas police said there were at least 10 firearms in his hotel room, including “long rifles.”

Typical military-style rifles are semi-automatic and are not capable of automatic fire, but they can be illegally altered to do so. Nevada does not restrict this popular type of semi-automatic weaponry, nor does it limit high-capacity magazines. Most states don’t.

Nevada also is what’s called a “shall issue” state for concealed carry permits, meaning that anyone who is qualified to possess a handgun under state and federal law will be approved to get one. The state legislature rolled back handgun registration requirements in 2015, which gun advocates saw as a positive move to keep firearms owners from having to fill out additional paperwork.