A doctor trying to return home was dragged by his hands from an overbooked United Airlines flight, embroiling the carrier in a second public relations nightmare in less than a month.

The airline was one of the top-trending topics on Twitter as users took to the website to express their anger over the forceful removal of the passenger from United Flight 3411, which was en route from Chicago to Louisville, Kentucky, on Sunday.

Video of the incident posted to Twitter account @Tyler_Bridges shows three security officers huddling over the seated passenger, who appears to be an older Asian man, before dragging him on the floor.

In a separate tweet, Bridges wrote that the man was removed because additional United crew needed to get to Louisville.

United said in a statement provided to some media outlets that the flight was overbooked.

“After our team looked for volunteers, one customer refused to leave the aircraft voluntarily,” United spokesman Charlie Hobart said. “We apologise for the overbook situation.”

“This is an upsetting event to all of us here at United,” chief executive officer Oscar Munoz said in another statement. “I apologise for having to re-accommodate these customers.”

Mr Munoz said United was “moving with a sense of urgency” to work with the authorities and conduct its own review of the incident.

In the @Tyler_Bridges video, a woman can be heard asking “Can’t they rent a car for the pilots and have them drive?” before two of the uniformed men reach into the passenger’s seat and yank him out.

Passenger screams

The passenger screams as he is dragged on his back by his hands, glasses askew and shirt pulled up above his navel.

Another video shows him, still dishevelled from the altercation, returning to the cabin, running to the back of the plane and repeating: “I have to go home.”

Fellow passenger Jayse D Anspach, who goes by @JayseDavid on Twitter, wrote: “No one volunteered (to leave), so @United decided to choose for us. They chose an Asian doctor and his wife.”

When the passenger refused to disembark, “a couple of airport security men forcefully pulled the doctor out of his chair and to the floor of the aisle”.

‘Serious bleeding’

The man’s face “was slammed against an arm rest, causing serious bleeding from his mouth”, wrote Anspach.

“It looked like he was knocked out, because he went limp and quiet and they dragged him out of the plane like a rag doll.”

Late last month, two teenage girls dressed in leggings were denied boarding on a United flight from Denver to Minneapolis because of their form-fitting pants.

Because the girls were using free passes for employees or family members, they were subject to a dress code.

Reuters