DALLAS — It might seem obvious to not pack a firearm in a carry-on bag when flying. 

However, the number of firearms collected at Transportation Security Administration checkpoints in the U.S. continues to rise.   

Last year, TSA collected a record number of 4,239 firearms at checkpoints. That translates to just under 12 firearms collected every day at U.S. airports. Passengers can travel with firearms in their checked bags, but they have to be declared beforehand.  

Both Dallas Fort Worth International Airport and Dallas Love Field Airport ranked in the Top 10 for the airports where TSA collected the most firearms last year. DFW was No. 2 with 219 firearms collected and Love Field was No. 9 with 89. 

Elsewhere in Texas, George Bush Intercontinental Airport and Austin-Bergstrom International Airport also had a spot in the Top 10.   

Firearms aren't the only strange thing TSA finds at checkpoints.  

You can take a look at some of TSA finds the agency shared on Instagram by clicking here.  

This fall, TSA’s Instagram account surpassed 1 million followers. The agency is known for injecting humor into the discussion around flying safety, whether it be through a meme or a caption typically not seen on a government account.   

For example, during National Talk Like A Pirate Day this September, the TSA account posted a picture of a replica grenade a passenger tried to travel with. Replica or inert grenades are not allowed in either carry-on or checked bags. 

"Wha' was this scallywag thinkin'? Inert or replica grenades aren't allowed at all in an airport," the caption reads. "We’ll be sayin’ walk th’ plank if ye try t' brin' this… ye may be arrested."  

When a passenger brings something prohibited to the airport or TSA checkpoint, a couple of things can happen.  

For firearms, TSA calls local law enforcement and they take possession of the weapon and determine if there will be criminal charges. TSA can assess civil penalties up to $13,669. 

For things like pocket knives, passengers have a couple of options. They can run it back to their car or some airports have mail kiosks where they can mail it to themselves. Or, they can surrender it to TSA. 

"The best thing is to not bring those items to the checkpoint in the first place," said TSA spokesperson Carrie Harmon. 

If the property is surrendered, TSA turns the item over to the Texas state surplus store. Items collected in the Dallas-Fort Worth area are brought to the Austin store, Harmon said. TSA itself doesn't sell the items.  

Passengers unsure if an item is allowed to fly can snap a photo and send a Tweet to @AskTSA to ask the agency if it's safe to bring on either a carry-on or checked bag. 

More on WFAA: