The video above from a 2022 report about Texas' gun laws.
TSA posted to Twitter that the 84-millimeter caliber weapon found was not declared, which is a requirement when traveling with firearms.
TSA didn't say exactly what type of weapon it was, but the large firearm resembles a Carl-Gustaf M4 recoilless rifle, used for combat and military purposes for "neutralizing armored tanks," according to its website.
It is unclear if any arrests were made or why the passenger was traveling with a military-style weapon.
Security protocol necessitates that firearms must be unloaded and locked in a hard-sided container and transported as checked baggage only. All passengers must declare every firearm and/or ammunition, which is prohibited in carry-on baggage, to the airline when checking their bag at the ticket counter.
You can speak with the TSA Contact Center with questions you have regarding TSA firearm regulations and for clarification on what you may or may not transport in your carry-on or checked baggage.