It's all fun and games until someone lets the cat out of the bag. Only, it seems the staff at British Airways wasn't even slightly amused after discovering a feline stowaway on board a plane slated to fly from Glasgow to London on Sunday.

So incensed were the attendants they punted the cat and its owner, a woman from the U.S. off the flight, even after the passenger insisted that she needed the furry quadruped for emotional support. British Airways policy dictates that cats don't qualify as emotional support animals and are not allowed in the cabin, but are stowed in the luggage hold elsewhere on the plane.

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The debacle started when the woman was asked to store her bag in the overhead compartment. When she was reticent about the request, that's when attendants discovered the cat in her carry-on bag. After staff removed her from the plane, the woman reported did not opt for a different flight.

Just as mystifying was how the cat, which was in her luggage ever since the woman arrived at the airport, managed to make it through security, especially with the high-tech scans that normally check for hazardous materials. Security personnel said that the cat would not have been detected, regardless of whether it was alive, dead or even a stuffed replica.

Although British Airways doesn't recognize cats as support animals, it does acknowledge dogs as support and assist animals for the disabled. Those canines can travel with passengers for free, usually huddled underneath the seats during the flight. Other animals have to be transferred as cargo in a temperature-controlled environment. While there's a fee for handling such pets, passengers must make arrangements in advance with British Airways' sister company IAG Cargo.

Policies regarding emotional support animals do vary according to the airline, with most of them trying to stress clarity in the wave of some bizarre instances of passenger claims regarding their pets. Earlier in October, a woman failed to convince Frontier Airlines attendants that her squirrel was an emotional support animal and was taken off the flight. In January, a similar fate awaited a United Airlines passenger trying to keep a peacock in the cabin for the same reason.

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