MIAMI — This Monday, a dog deceased in United Airlines’ flight 1284 from Houston (IAH) to New York’s LaGuardia Airport (LGA) after being placed, throughout the entire trip, in the overhead bin.

According to passengers onboard the flight, a flight attendant asked the pet’s owner to place it in the overhead bin.

“I just flew into LGA and witnessed a United flight attendant instruct a passenger to put her dog bag in the overhead bin,” passenger Maggie Gremminger wrote on Twitter.

“It was clearly a dog and while the customer was adamant about leaving it under the seat, the attendant pushed her to do so.”

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Gremminger added that “myself and a fellow passenger felt like that was NOT a thing,” questioning about ventilation inside the aircraft’s overhead bins.

In addition, 11-year-old Sophia Ceballos, who is the daughter of the pet’s owner, told ABC News:

“The flight attendant came, and she was like, ‘You have to put him up there because it’s going to block the path’. And we were like, ‘It’s a dog! It’s a dog!’ And she said, ‘It doesn’t matter, you still have to put it up there.’”

The 10-month-old French bulldog, named Kokito, complied with all the requirements and conditions to travel onboard the aircraft with its owner in the cabin.

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The Houston – New York route lasts three hours and 30 minutes, approximately. While passengers heard the dog’s bark during the flight, the owners realized it was dead after retrieving the kennel from the bin.

Furthermore, in a statement United Airlines shared:

“This was a tragic accident that should never have occurred, as pets should never be placed in the overhead bin. We assume full responsibility for this tragedy and express our deepest condolences to the family and are committed to supporting them. We are thoroughly investigating what occurred to prevent this from ever happening again.”

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United’s policy on animals reads:

“A pet traveling in cabin must be carried in an approved hard-sided or soft-sided kennel. The kennel must fit completely under the seat in front of the customer and remain there at all times.”

As of today, the incident has induced sadness, outrage, and shock worldwide. The Chicago-headquartered carrier is still investigating the matter.