Licensed gun owners who bring their firearms to the security checkpoint at Hartsfield-Jackson International Airport will generally end up in Clayton County jail. But they’re free to carry them anywhere else in the terminal, ever since a 2010 state law allowed it.

Hartsfield-Jackson has now become the No. 1 airport in the nation for the number of guns found at security checkpoints. Last year, 100 guns were found and so far this year, 67 have been found in carry-on bags — on pace to top last year.

“Everybody that carries a firearm should know that it can’t be carried there [through security],” said Jerry Henry, executive director of GeorgiaCarry.org, which advocates for gun owners’ rights. “If anybody is caught, it’s carelessness.” The cost can be a night in Clayton County jail, nearly $2,000 in bail and fines, and a year of probation, he said.

The sheer number of travelers going through the Atlanta airport contributes to the number of guns found. Yet while it has the most guns turned up, it doesn’t have the most travelers going through security.

Hartsfield-Jackson is the world’s busiest airport because of its heavy connecting traffic, but it is only No. 5 when ranked by the number of passengers screened at security checkpoints. Los Angeles, New York John F. Kennedy, Chicago O’Hare and San Francisco all have more passengers going through security than Atlanta.

At Hartsfield-Jackson, the numbers mean that on average, someone tries to take a gun through security a couple of times a week — which airport manager Louis Miller wants to curb. Miller and police officials say it increases wait times for passengers in line because the lane is shut down, and takes up time and resources of law enforcement who handle the offender and the arrest.

“It’s just very disruptive to us,” Miller said. To combat the issue, the airport has put up signs to remind passengers that guns are prohibited through security checkpoints. At a news conference Thursday, Miller and police officials warned that offenders will miss their flight, be taken to Clayton County jail and be subject to prosecution and fines.

Tussles between the city-run airport and the state over whether guns should be allowed in the terminal have gone on for years.

After a state law took effect five years ago allowing guns in state parks, on mass transit and in restaurants that serve alcohol, then-airport manager Ben DeCosta declared the airport a gun-free zone and threatened to arrest anyone found with a gun at the airport — setting up a legal fight.

The city lost its say in the matter in 2010, after the state law was passed allowing guns in the airport terminal.

Now, the airport is caught between state law allowing guns in the terminal and federal law disallowing guns through security — while the city-run airport has little control over either.

At one point, the airport had signs on doors to the domestic terminal saying guns are prohibited. But earlier this year, the airport responded to a complaint and removed those signs, acknowledging that they now contradict state law.

Then, a few weeks ago, Hartsfield-Jackson officials put up even bigger signs prohibiting guns and other weapons in 30 locations at security checkpoints — where federal law bans them.

Alice Johnson, executive director of Georgians for Gun Safety, thinks that as laws are liberalized to allow guns in more locations, “people are going to be always forgetting that there are places where they can’t carry a firearm.”

Sen. Nan Orrock, D-Atlanta, who believes the state’s gun laws are too lenient, said she can imagine that if “you’re carrying a gun night and day … you actually take it for granted that you can go anywhere with it.”

The patchwork of gun regulations across the nation can be confusing for travelers — and some have even legally put guns in checked bags at one airport, such as Atlanta’s, only to be arrested later for having the gun in a jurisdiction with more restrictive gun laws, such as New York.

“I think most people know that if you’re going to New York, there’s no reciprocity” for other states’ gun licenses, Henry said. “If you’re going to carry a firearm, you need to carry it responsibly, and you need to know what the laws are.”