A record number of guns were found in passengers' carry-on luggage at airport security checkpoints during one week in September, according to the Transportation Security Agency.
TSA agents discovered 67 guns in carry-on luggage in airports across the country during the week that ended Sept. 17, according to the agency, which said the tally for the week broke a previous record of 65 firearms found during one week in May 2013. Of those 67 guns, 56 were loaded and 26 had a round chambered, according to the TSA.
Throwing stars, stun guns, gunpowder and belt buckle knives were also found during the second full week in September, the TSA said.
"Unfortunately these sorts of occurrences are all too frequent which is why we talk about these finds ... This is a friendly reminder to please leave these items at home," the TSA says in its weekly disclosure of weapon discoveries. The TSA adds that most passengers who pack heat in their carry-ons have "no ill intent."
"In many cases, people simply forgot they had these items," according to the TSA.
Guns and gun parts are prohibited in carry-on luggage, but passengers can check these items if they declare them with the airline, according to the TSA. Those who don't follow the guidelines can face fines up to $11,000.
TSA officers found nearly 1,900 firearms in carry-on luggage between Jan. 1 and Aug. 31, 2015, according to TSA data shared with NBC News. This year is on track to see a 28 percent spike in the number of firearms found compared to the 2,212 guns — an average of about 40 a week — discovered by TSA agents in 2014.
Twenty-two percent more guns were found in 2014 as compared with 2013, according to the data.
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It's unclear whether more people are traveling with guns or if TSA agents are being more vigilant. A TSA spokesman declined to comment on the matter.
The Department of Homeland Security in June announced that an undercover test found 67 out of 70 weapons got past TSA agents. The 95 percent failure rate led to the reassignment of the acting head of the TSA.
The new TSA administrator, Peter Neffenger, said at a subsequent House Homeland Security hearing that his goal was to "train out those failures" by the end of September.