A record number of firearms was discovered in carry-on bags in the U.S. in 2016, the Transportation Security Administration says.

In total, 3,391 firearms were found in carry-on bags at TSA checkpoints across the country — averaging more than nine per day and amounting to a 28 increase in firearm discoveries from 2015, when 2,653 were discovered, the TSA said in a blog post on Thursday.

Eight-three percent of firearms found at TSA checkpoints last year — or 2,815 — were loaded.

“The number one excuse that we hear is that they forgot that they had it with them,” TSA official Lisa Farbstein said, CBS Baltimore reported. “The second most common excuse we hear is that their wife or husband packed their bag. And I tell you what, neither of those excuses fly.” 

Atlanta’s Hartsfield-Jackson international airport was no. 1 on the list of top airports for firearms discoveries, with 198 guns being found by TSA agents.

Firearms were intercepted at a total of 238 airports, with Dallas/Fort Worth International Airport, Houston’s George Bush Intercontinental Airport, Phoenix Sky Harbor International Airport and Denver International Airport rounding out the top five airports for firearms discoveries. Orlando International Airport, Nashville International Airport, Tampa International Airport, Austin-Bergstrom International Airport and Salt Lake City International Airport completed the top ten list.

Data from the TSA shows that the number of firearms found nationwide has increased almost every year since 2005, when 660 were discovered. The only drop was from 2006 to 2007 — from 821 discoveries to 803.

The issue of firearms at airports caught lawmakers’ attention after a fatal shooting earlier this month at Fort Lauderdale’s airport. Lawmakers are taking a new look at rules about guns on planes following the rampage, which unfolded in baggage claim.

The TSA allows guns in checked baggage, CBS News correspondent Tony Dokoupil reported. They have to be unloaded and locked in a hard-sided container, and owners have to declare them at the ticket counter. 

“We’re going to have to take a hard look once and for all at the unsecured areas of our airports,” Rep. Debbie Wasserman Schultz, D-Fla., said.

Wasserman Schultz said she plans to review security procedures with TSA leaders. 

Some travelers last year also attempted to bring gun powder on planes, and officers uncovered inert grenades in carry-on and checked luggage, the TSA said. Inert items can lead to closed terminals and checkpoints, and the problem with the items is that the TSA doesn’t know if they’re real, replicas or toys until explosives experts are called upon, the TSA said.

That wasn’t all that officers found in 2016.

“There were many instances last year when travelers attempted to hide items, or the items they packed were disguised to look like other items,” the TSA said. “TSA officers regularly find sword canes, credit card knives, belt buckle knives, comb/brush knives, knives hidden in shoes, knives hidden in thermoses and knives hidden under the bag lining near the handle mechanism.”

TSA officers screened 466 million checked bags, 24.2 million airport employees and 738,318,264 passengers in 2016, which is more than 43,255,172 more passengers than for the same time frame in 2015, the TSA said.

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