The number of guns stolen from Colorado gun dealers more than doubled in 2016 – reaching a 10-year high – according to the Federal Bureau of Alcohol, Tobacco, Firearms and Explosives.

Often, those guns end up being used in other crimes.

A 9Wants to Know investigation found a common denominator in thefts from Colorado gun dealers – widely varying practices for securing weapons when the shops were closed, something that is not covered by any federal requirements.

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For example, some of the guns were taken in “smash-and-grabs” where the weapons were displayed in breakable cases, tied by metal wire, but not put away in a safe overnight. 9Wants to Know found there are no federal requirements or mandates for security in gun stores.

In one case in Parker, 9Wants To Know found the burglars didn’t have to enter the store. According to the police report, the burglars smashed the window and took the long guns from their display.

In 2016, the ATF says 273 guns were stolen compared to 121 guns stolen from Colorado gun dealers in 2015 and 56 in 2014.

“We are very concerned about the rise in gun thefts,” said ATF Denver Field Division Special Agent in Charge Debbie Livingston. “These guns will not be used for hunting or sport; they are destined for future crimes and are a threat to public and officer safety.”

According to the National Sports Shooting Foundation, a trade association for the firearms industry representing more than 12,000 manufacturers, distributors, retailers, ranges and other organizations, the stores that sell guns don’t have any mandated security requirements.

“It’s a balancing act,” Mike Bazinet said, director of public affairs for NSSF. “For sure, retailers take their discussions with law enforcement very seriously.”

ATF and local law enforcement can make suggestions to gun stores on how to improve their security.

Not all of these stores are “deep pocket operations,” Bazinet said. “We’ve seen stores with significant security that have still been penetrated by burglars. We’ve seen increased aggressiveness on the part of burglars across the country.”

Livingston said the gun dealers themselves are victims of these crimes.

“They’re having their stores broken into, glass broken, firearms stolen, they are true victims and at some point, you’d think, they no longer want to be victims,” she said. “What we have seen that dealers that have installed additional measures, if they are being burglarized, nothing gets taken, so that speaks for itself. There’s been a few attempts where they can’t get anything.”

9Wants to Know looked at a sample of Colorado gun store burglaries from 2016 and found that security, as well as the way the guns are locked up at night, vary from retailer to retailer.

The stores are targets for burglars, even with an alarm and local law enforcement just minutes away.

That’s what happened at Colorado Gun Brokers in Jefferson County June 21, 2016 where investigators say about 30 guns were stolen from a glass display case and the wall display in less than six minutes. That’s how long it took Jefferson County Sheriff’s office to be on site. The store had an active alarm system, but the burglars were able to get through the glass front door and the metal security gate.

“[The security] definitely should’ve been better,” Josh Rayburn, owner of Colorado Gun Brokers told 9Wants To Know, “ultimately because they got away with a lot of guns. That’s the last thing any gun shop owner wants to happen. Because we do a lot of security measures in store to try to minimize the risk of firearms getting into the wrong hands. When someone breaks in and steals a bunch of guns, who knows who’s getting them now, that’s what upset us the most.

Rayburn told 9Wants To Know his old store location had walk-in safes. The new location where he’s been for a couple of years, didn’t have the space to lock up everything.

The store used to display merchandise in cases with metal cable with a pad lock on the end. Rayburn said he thought that and outside security measures were enough. He admitted they weren’t. He’s since changed his security procedures and the store now has a safe.

But having top notch security didn’t help the owner of Jumping Jack Cash in Thornton. His pawn shop was burglarized August 23.

“If they want it bad enough, they’re going to get it,” owner Todd Hills said. “These guys that came in on us in the middle of the night were very sharp, they obviously knew what they were doing, they cut security cameras, they came over the top of the vault down into the vault and there were no cameras. They were very good.”

Hills, who owns several pawn shops, already had gun sales consolidated to his Thornton location. But after this last burglary, he’s out of the gun sale business.

“When you look at the profitability versus the liability, just doesn’t make sense,” Hills said. “We feel like without the presence of guns in our stores our employees are much safer, our customers are much safer and we just have less headache to deal with.”

Hills said the gun cases used for displays should not be easy to break and the guns should be put away at night.

“It’s my opinion that if you’re a firearm dealer, you have a responsibility to keep those guns safe, keep control of those guns and if you don’t put them away at night at the end of the day – you’re lazy,” Hills said. “It does take time to put these guns away at night, it does take time to secure them, it costs money to secure them, you gotta beef up your vaults, you gotta beef up your camera systems, your alarms, you gotta do everything, but that’s the cost of doing business, if you’re going to deal with firearms, that’s your cost of doing business.”

Smaller gun dealers aren’t the only targets for burglars.

Five rifles and shot guns were stolen from the Bass Pro Shop in Denver last March. According to investigators, the juvenile suspects smashed the glass case and pried open the gun rack.

When Triple J Armory in Littleton was burglarized on June 22, the suspects took about 30 guns. Littleton Police told 9Wants to Know, the suspects drove a truck through the front of the store. Three suspects grabbed the firearms off the display, “the guns that were stolen were not secured,” police said.

About a month later, on July 14, a gun from that burglary was used by a teen boy to shoot another boy in Edgewater. According to the police report obtained by 9Wants to Know, the shooting was an accident. The teen survived and the suspected shooter was arrested.

He had three active warrants, including one nationwide. He allegedly told police he was a gang member.

Robert Troyer, Acting U.S. Attorney for the District of Colorado, says his office partners with local law enforcement and prosecutors to ensure maximum sentences for gun store burglars.

“These folks who are brazenly driving cars through store fronts, swooping up 10, 20 in one case I think 35 weapons at a time, putting them in the hands of other criminals immediately afterward are causing again downstream enormous harm to communities,” Troyer said. “Reducing violent crime is a top priority of the Department of Justice right now and after terrorism these kinds of crimes are my office’s highest violent crime priority.”