An average of nine firearms a day were confiscated at US airports last year – most of them loaded – according to figures released by the Transportation Security Administration (TSA).

The agency, which has become an unlikely hit on Instagram, discovered a total 3,391 guns on travellers in 2016, 83 per cent of which, it said, were loaded.

A photo posted by TSA (@tsa) on Nov 22, 2016 at 8:02pm PST

That figure represents a 28 per cent increase on 2015 statistics, compared to a 6.2 per cent rise in the number of passengers screened by the TSA.

The agency also revealed the 10 airports with the most firearm discoveries; a list topped by Hartsfield-Jackson Atlanta International Airport (ATL).

Top 10 US airports for firearm discoveries Hartsfield-Jackson Atlanta International Airport (ATL) Dallas/Fort Worth International (DFW) George Bush Intercontinental Airport - Houston (IAH) Phoenix Sky Harbor International (PHX) Denver International (DEN) Orlando International Airport (MCO) Nashville International (BNA) Tampa International (TPA) Austin-Bergstrom International Airport (AUS) Salt Lake City International (SLC)

TSA rules prohibit guns in carry-on bags, but they do allow passengers to travel with firearms provided they are unloaded, stored in a hard-sided, locked container and placed in a checked bag.

Travelling with prohibited items will not only cause delays at the airport, warns the TSA, but could also land you with a criminal conviction.

“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,” said the TSA. “The passenger can face a penalty as high as $11,000 (£8,800).”

The arsenal of deadly weapons confiscated by the TSA – including guns, grenades and hatchets – is somewhat unnerving, but the agency has also intercepted some more bizarre items including a life-sized dummy from the film Texas Chainsaw Massacre.

In pictures: Bizarre smuggling attempts that went wrong

Such discoveries are regularly shared on Instagram by the TSA, which was recently named by Rolling Stone as one of the world’s best Instagrammers, beating Beyonce into fourth place. Kim Kardashian, National Geographic and Rihanna came first, second and third respectively.