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Labor Day weekend was a busy one for Transportation Security Administration personnel at Hartsfield-Jackson Atlanta International Airport.

Atlanta's WSBTV reported that three firearms and a grenade were uncovered by security screeners over the weekend. 

The slew of seizures began when a loaded 9mm handgun was found in a passenger's carry-on bag at the airport's main checkpoint at 10:15 a.m. local time Friday. Screeners then discovered a loaded .25 caliber firearm at the airport's north checkpoint an hour later.

Another 9mm was seized at the main checkpoint shortly before 8 p.m. local time Friday night.

The alarming weekend of weapon seizures culminated at 9:30 a.m. local time Monday when TSA officers uncovered an inactive grenade in a carry-on bag at the main checkpoint. 

The high volume of weapons discovered prompted a friendly reminder from the agency. 

"Passengers are responsible for the contents of bags they bring to the checkpoint," TSA regional spokesman Mark Howell told WSBTV. "Our advice is to look through bags thoroughly before coming to the airport to make sure there are no illegal or prohibited items."

The number of firearm seizures at U.S. airport checkpoints has been climbing in recent years and 2015 is on pace to set a new record. 

"This just kind of highlights the trend nationwide of firearms being brought to checkpoints," Howell added, pointing out that, "about 80 to 90 percent of the time, the firearms are loaded."

Last year, a record 2,212 firearms were seized from carry-on luggage across the nation. While Atlanta ranked second behind Dallas/Fort Worth International Airport with 109 total seizures in 2014, the airport is on pace to shatter that mark, with screeners confiscating 106 firearms at checkpoints so far this year. 

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