Airport security staff were baffled when an X-ray image came up showing a pet cat tucked inside a piece of carry-on baggage.
A traveller at Norfolk International Airport in Virginia, US, had the feline in their carry-on bag which was also a pet travel case.
The X-ray photo was released on Twitter by Lisa Farbstein, a Transportation Security Administration (TSA) spokesperson.
The TSA reminded pet owners not to send their pets through the X-ray machine.
Ms Farbstein said: "When that happens, they have to start all over again, meaning that the passenger and the cat have to start over at the checkpoint."
She wrote on Twitter: "Just when you thought it was safe to bring your pet cat on a trip. . . A traveller left their pet cat in its travel carrying case at a @TSA checkpoint this morning at @NorfolkAirport.
"Attention pet owners: Please do not send your pet through the X-ray unit. Cat-astrophic mistake!"
The TSA recommends that cats be taken out of their cases and walked through the metal detector on a leash.
If no leash is available, cats can be screened in a private room at the request of their owner, as they can be more skittish than dogs and might scratch, bite, or try to run away.
Ms Farbstein told CNN: "The passenger needs to remove the pet from a carry case and carry it through the walk-through metal detector or walk the pet through the metal detector on a leash.
"This is typical of how people travel with small dogs. In the case of a cat, if there is no leash, we strongly recommend that the passenger requests screening in a private screening room."
Many Twitter users responded to the X-ray image expressing concerns for the welfare of the cat.
Someone said, "Is the cat okay?" to which Ms Farbstein replied: "Yep. The traveller and cat had to go through screening the proper way once the TSA officers saw the X-ray image. The proper way being to remove the cat from the travel bag."
Others appreciated the fun in the situation and commented: "Hopefully this will be a "cat-alyst" for change....." and "Getting a CAT scan on a budget."
