CHICAGO: United Airlines is facing backlash after footage of a man being forcibly removed from a Louisville-bound flight from Chicago surfaced on social media. 

According to an account by passenger Audra Bridges posted on Facebook on Monday (Apr 10, Singapore time), United Airlines had overbooked the flight and "randomly selected" people to be taken off the plane so that standby crew could have a seat.

United representatives had initially asked for volunteers and offered passengers US$800 to give up their seat, Ms Bridges told the Louisville Courier-Journal.

She said two passengers gave up their seats willingly but the man, who said he was a doctor, would not, saying he had patients to see in the Louisville area in the morning. 

In the video posted by Ms Bridges which has since been shared more than 1,500 times, men in uniform grab an Asian man from his seat and he puts up a struggle and screams. They then yank him into the aisle and drag him by his arms off the plane.

Passengers look on, horrified. One woman is heard saying: "My God, no! What are you doing?"

As passengers catch sight of his reddened face, glasses askew, she says: "This is wrong. Look at what you did to him!"

"We are all shaky and so disgusted," Ms Bridges said in her account.

Her partner, Tyler Bridges, who posted the same video of the incident on Twitter, wrote "not a good way to treat a doctor trying to get to work because they overbooked". He also said "kids were crying, people are disturbed". 

He posted follow-up video of the incident showing the man running back onto the plane and repeating "I have to go home."

The plane departed Chicago's O'Hare International Airport two hours behind schedule, according to flight tracker FlightAware.

Responding to questions from media on Twitter, the airline said: "We apologise for the overbook situation. Further details on the removed customer should be directed to authorities."