A 22-year-old Maryland man was arrested at Baltimore Washington International Airport last week after Transportation Security Administration (TSA) officials discovered a collapsible rifle in his carry-on bag.

According to TSA, the .40 caliber rifle, which was not loaded, was detected by a TSA officer as the luggage went through an X-ray machine on Oct. 12.

TSA subsequently contacted the Maryland Transportation Authority Police, who confiscated the gun and arrested the man. He told authorities he was unaware the firearm was in his bag because his mother had packed it for him.

Regardless, TSA hopes the incident serves as another reminder to travelers about the perils of bringing guns through airport security.

"Individuals who bring firearms to the checkpoint are subject to possible criminal charges from law enforcement. Even travelers with firearm permits are not allowed to bring guns onto airplanes," the agency states. "In addition, TSA has the authority to assess civil penalties of up to $13,000 for weapons violations. A typical first offense for carrying a handgun into a checkpoint is $3,900."

Passengers who fail to follow the rules are also likely to draw the ire of their fellow travelers.

"When someone brings a firearm to a checkpoint, it closes the checkpoint lane until the situation can be resolved, thus forcing the other travelers to shift into another lane and delaying their passage through the checkpoint," TSA added.

The gun is the 20th officers have caught at BWI Airport checkpoints this year. More than two dozen firearms were detected at the airport a year ago. Still, BWI pales in comparison to Hartsfield-Jackson Atlanta International Airport, where a stunning 245 guns were detected last year.

A record-setting 3,957 firearms were discovered in carry-on bags at U.S. airport checkpoints in 2017, up nearly 17 percent from 3,391 the previous year. Of those nearly 4,000 guns confiscated last year, an astounding 84 percent were loaded and 34.8 percent had a round in the chamber.