Two people and their emotional support dogs were removed from a flight due to the dogs "showing signs of distress in the cabin", Norwegian Air said on Thursday.
The flight from Gatwick Airport in London to Austin, Texas had not yet departed when the captain decided to offload the emotional support dogs and two owners.
“The safety and security of our passengers and crew is always our number one priority," a Norwegian Air spokesman said.
Emotional support dogs help people with mental or emotional disabilities and are only permitted in the cabin on direct flights to and from the US, Norwegian Air says on their website.
But this excludes flights going to the United Kingdom. In order to travel on flights to the United Kingdom, an emotional support dog must have specific training and a certification "from an accredited body for assistance dogs worldwide", according to Norwegian Air.
The flight took off 20 minutes later than scheduled, according to Flightview.
"The support dogs were fully verified and met all requirements, including passports and paperwork, when passing through airport security and boarding," a Gatwick Airport spokesman said in a statement.
This documentation also likely included a letter from a mental health professional stating that the passenger needed the emotional support animal for air travel or at the destination, in line with Norwegian Air's requirements for emotional support dogs.
Photos of the dogs that circulated on Twitter appeared to be either blocked or taken down at the time of writing.