A disturbing video appeared on social media recently of a passenger being violently dragged down the aisle of a united airlines Plane on Sunday as it was about to fly out of Chicago. According to one of the passengers, flight crew had said they could not take off until four people volunteered to disembark, as they had overbooked the flight.

Male passenger dragged screaming down the aisle

In the video the male passenger can be seen to be dragged by security personnel out of his seat and his head hits an armrest. To the shock of other passengers on the flight, the man is then dragged on his back down the aisle of the plane, with blood pouring from a split lip.

Many people took video footage of the United Airlines incident on their phones and posted it to social media.

One woman can be heard to shout out, asking security staff what they are doing and saying this was wrong. She asks them to look at what they did to the man, exclaiming, “Oh my God!” Other passengers shouted at the officers to stop what they were doing to the man. It is clearly apparent from the video how upset other passengers were about what was happening.

Four ‘volunteers’ need to leave the plane

The Courier-Journal spoke to Audra D.

Bridges, who posted a video of the incident on Facebook, and she explained that airline staff wanted people to volunteer to give up their seat on the flight as it boarded. United Airlines reportedly offered the volunteers $400, along with a hotel stay. The reason for the overbooking was that reportedly four United employees needed to be in Louisville on Monday and they had to make seats available for them.

When no one volunteered to leave the flight, the airline reportedly increased the monetary offer to $800, again stating that the flight would not leave until they could get rid of four passengers. Still no one was willing to volunteer.

Airline staff then said a computer would decide which four people should get off the plane. Of the people randomly selected by the computer, one couple was willing to cooperate and left the plane.

Man dragged off plane was a doctor

However, the third person selected was the man in question, who refused to leave the United Airlines flight. According to the post on Facebook by Bridges, he is a doctor and had to be at a hospital the next morning.

United Airlines later apologized in a statement for the incident, saying they were sorry about the “overbook situation.” The Huffington Post reportedly contacted the airline to ask if it is normal airline policy to call security staff when a passenger refuses to “volunteer” to leave the plane, but reportedly got no response.

The incident caused major outrage on social media, with many Twitter users telling United Airlines they will never fly with them again. #DontFlyUnited is now the "go-to" hashtag.

However, it looks like Delta Air Lines' recent generosity during bad weather flight delays has paid off. That airline gave their passengers free pizza.