Bart Jansen

USA TODAY

Agents found 20%25 more guns in 2013

84%25 of the weapons found were loaded

The most popular weapons found were .380-caliber and 9 mm handguns

The Transportation Security Administration continues to find more guns each year in passenger carry-on bags, to the point that agents uncover roughly five guns every day in a U.S. airport, according to a new study.

TSA found 1,828 guns among travelers preparing to board planes in 2013, a 20% increase from the year before, according to an analysis of agency data by Northwestern University's Medill National Security Journalism Initiative.

The rate represents a steady increase from the 1,123 firearms found in 2010, according to the analysis.

"TSA takes the discovery of prohibited items seriously and urges all passengers to check the contents of their bags before leaving home to ensure they are not bringing any prohibited items to the airport — including firearms, firearm parts and ammunition," the agency said in a statement Monday.

Jeffrey Price, who follows aviation security as a professor at Metropolitan State University in Denver, said travelers have become more relaxed as the terrorist hijackings Sept. 11, 2001, recede into history.

"I think some people think they're not paying as much attention anymore," Price said. "Also, I think the majority of the problems are with people who don't fly that often. You get folks who have a concealed-carry permit, they're used to having their gun and they don't think twice about it."

The expansion of risk-based screening, such as Pre-check, which focuses greater scrutiny on less-frequent travelers, might also contribute to finding more contraband.

"They're getting better at identifying items quicker," Price said.

About 84% of the weapons found were loaded, and one in three had a bullet in the chamber ready to fire, according to the study. The most popular weapons found were .380-caliber and 9 mm handguns.

The problem with finding loaded weapons continued Saturday at Greater Rochester International Airport, where TSA officers found a loaded pistol holstered in a man's carry-on bag. Monroe County sheriff's deputies at the checkpoint confiscated the gun.

A TSA blog, which provided the information that the Medill analysis is based on, illustrated how many guns are found with the year's final installment. For the week ending Dec. 27, TSA found 31 firearms, with 25 loaded and seven with rounds in the firing chamber, according to the blog.

The totals might change slightly because the weekly blog isn't updated when a report comes in after deadline. For example, Medill counted 1,525 guns in 2012 and TSA totaled 1,556 that year. TSA hasn't finalized 2013 yet but counted 1,750 through Dec. 17.

Federal regulations prohibit carrying guns in a plane's cabin. To bring a gun on a trip, it must be unloaded in a secure container in checked baggage.

TSA doesn't make arrests when guns are found at a checkpoint but refers the traveler to local law enforcement officers. Depending on local laws, the passenger could be arrested, given a ticket or allowed to store the gun before passing through security. Besides criminal charges, TSA can impose civil fines ranging from $250 to $11,000.