According to the United’s official in-cabin pet policy, animals must be in a carrier and “fit completely under the seat in front of the customer and remain there at all times.” There is no mention of using an overhead bin.

United has released a statement taking full responsibility and says it’s looking further into the incident:

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.

This is just the latest in a string of troubling episodes for United when it comes to transporting pets.

The airline issued a similar apology last August when a dog died in the cargo hold of a plane that was delayed on the tarmac for two hours with temperatures over 90°F inside. Last June, rapper SchoolBoy Q accused United of putting his pet dog on the wrong flight to the wrong city during a layover. In April, a giant rabbit named Simon died on a United flight last April en route to the Iowa State Fair.

There is no word yet on the official cause of death, though United has offered to pay for a necropsy, as well as refunding the family’s tickets.

The airline has apparently learned a few things about crisis management since executives botched the response after a bumped passenger was dragged off a flight last April.

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