Harriet Baskas

Special for USA TODAY

Despite the Transportation Security Administration’s repeated reminders that “firearms, ammunition, firearm parts, and realistic replicas of firearms are prohibited from carry-on baggage,” last week travelers were found with a record-breaking number of guns at airport checkpoints.

From Aug. 5 to 11, TSA officers found 78 firearms in carry-on bags at U.S. airports.

That breaks a previous record set in May 2016, when 74 firearms were discovered at airport checkpoints, and one set a month earlier, in April 2016, when 73 firearms were found.

Of the 78 firearms found in carry-on bags last week, 68 were loaded and 21 had a round chambered.

Five firearms were found at checkpoints at both Tampa and San Antonio International Airports, while four passengers were found with firearms at checkpoints at Phoenix Sky Harbor International Airport.

“In many cases, people simply forgot they had these items,” the TSA notes on its blog, adding that “… each time we find a dangerous item, the line is slowed down and a passenger that likely had no ill intent ends up with a citation or in some cases is even arrested.”

Clearly, not all the firearms and other prohibited items the TSA finds in travelers’ carry-on bags are there by mistake.

Last week TSA officers found a knife tucked inside a pill bottle at San Francisco International Airport and, the week before that, TSA officers at Reno Tahoe International Airport found live ammunition loaded inside a gun made out of parts created on a 3D printer.

TSA has the authority to impose civil penalties of more than $12,000 per violation on travelers found with loaded or unloaded guns and realistic replicas.

And while passengers are not allowed to take firearms onboard airplanes, according to the team answering “Can I take my …” questions sent to @AskTSA on Twitter, shell casings, as well as sauerkraut and gel masks, are permitted:

Harriet Baskas is a Seattle-based airports and aviation writer and USA TODAY Travel's "At the Airport" columnist. She occasionally contributes to Ben Mutzabaugh's Today in the Sky blog. Follow her at twitter.com/hbaskas.