United Airlines have claimed "full responsibility" for a dog's in-flight death after a flight attended forced the owner to put the pet in an overhead locker. Kokito - a French bulldog puppy - sadly passed away during a flight from Houston to New York on Monday morning.

According to eye-witnesses, the flight attendant repeatedly asked Kokito's owner, Catalina Castano, to put her airline-approved carrier in the locker. And, despite her declining to do several times as there was a dog in there, the flight attendant claims that she had no idea that the animal was in the bag.

Magie Gremminger was a passenger on the plane and says that she was sitting behind the woman and the dog when the incident occurred.

"I was sitting in the row behind the woman with the dog, and the gentleman next to me witnessed it all as well.

"We both overheard/saw the interaction between the flight attendant and the passenger. I witnessed a United flight attendant instruct a woman to put her dog carrier with live dog in an overhead bin.

"The passenger adamantly pushed back, sharing verbally that her dog was in the bag.

"The flight attendant continued to ask the passenger to do it, and she eventually complied.

"By the end of the flight, the dog was dead. The woman was crying in the airplane aisle on the floor."

Gemminger went on to share a photo of the family on Twitter saying that "my heart is broken."

While overhead lockers are not air-tight, it's believed that the lack of oxygen is most likely the cause of  Kokito's death.

United's policy when it comes to bringing animals on board states that "a pet travelling 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."

United have accepted responsibility for the death and have said that they will start an investigation into the incident in order to make sure that it never happens again.

"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."

It's not the first time they United have landed in hot water when it comes to allowing animals on their flights. Last year, it was revealed that more animals died on-board United flights than any other major airline in the US. Data showed that nine pets died and 14 were injured during flights that took place in 2016.

"We have some of the best facilities for taking care of customer pets," said a spokesperson at the time.

"We keep customers informed and consider pets customers as well because we understand pets are part of our customers' family."

It's an absolutely horrific turn of events that was completely avoidable. Dogs are part of a person's family and to force the woman into sticking her pet in an over-head locker is completely unacceptable.

United Airlines have claimed "full responsibility" for a dog's in-flight death after a flight attended forced the owner to put the pet in an overhead locker. Kokito - a French bulldog puppy - sadly passed away during a flight from Houston to New York on Monday morning.

According to eye-witnesses, the flight attendant repeatedly asked Kokito's owner, Catalina Castano, to put her airline-approved carrier in the locker. And, despite her declining to do several times as there was a dog in there, the flight attendant claims that she had no idea that the animal was in the bag.

Magie Gremminger was a passenger on the plane and says that she was sitting behind the woman and the dog when the incident occurred.

"I was sitting in the row behind the woman with the dog, and the gentleman next to me witnessed it all as well.

"We both overheard/saw the interaction between the flight attendant and the passenger. I witnessed a United flight attendant instruct a woman to put her dog carrier with live dog in an overhead bin.

"The passenger adamantly pushed back, sharing verbally that her dog was in the bag.

"The flight attendant continued to ask the passenger to do it, and she eventually complied.

"By the end of the flight, the dog was dead. The woman was crying in the airplane aisle on the floor."

Gemminger went on to share a photo of the family on Twitter saying that "my heart is broken."

While overhead lockers are not air-tight, it's believed that the lack of oxygen is most likely the cause of  Kokito's death.

United's policy when it comes to bringing animals on board states that "a pet travelling 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."

United have accepted responsibility for the death and have said that they will start an investigation into the incident in order to make sure that it never happens again.

"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."

It's not the first time they United have landed in hot water when it comes to allowing animals on their flights. Last year, it was revealed that more animals died on-board United flights than any other major airline in the US. Data showed that nine pets died and 14 were injured during flights that took place in 2016.

"We have some of the best facilities for taking care of customer pets," said a spokesperson at the time.

"We keep customers informed and consider pets customers as well because we understand pets are part of our customers' family."

It's an absolutely horrific turn of events that was completely avoidable. Dogs are part of a person's family and to force the woman into sticking her pet in an over-head locker is completely unacceptable.