United Airlines landed in soup after video of a passenger being physically dragged off from an overbooked plane, United Flight 3411 from Chicago O'Hare International Airport to Louisville, Kentucky, surfaced on social media.

An Asian man could be seen screaming in the video as police officers pulled him from his seat on United Flight 3411.

According to media reports, one of the security officers involved in the case has been placed on leave as the investigation into the incident was launched.

A spokesman for the airline insisted that employees had no choice but to contact authorities to remove the man.

As the flight waited to depart from Chicago, officers could be seen grabbing the screaming man from a window seat, pulling him across the armrest and dragging him down the aisle by his arms. The airline was trying to make room for four of its employees on the flight.

Other passengers on Flight 3411 are heard saying, "Please, my God", "What are you doing? This is wrong", "Look at what you did to him" and "Busted his lip".

The man sustained injuries on his face as blood could be seen dripping down his mouth. He repeatedly said, "Just kill me. Kill me," and "I have to go home."

Passenger Audra D Bridges also posted a video on Facebook.

Her husband, Tyler Bridges, said United offered USD 400 and then USD 800 vouchers and a hotel stay for volunteers to give up their seats. When no one volunteered, a United manager came on the plane and announced that passengers would be chosen at random.

"We almost felt like we were being taken hostage," Tyler Bridges said. "We were stuck there. You can't do anything as a traveller. You're relying on the airline."

When airline employees named four customers who had to leave the plane, three of them did so. The fourth person refused to move, and police were called, United spokesman Charlie Hobart said.

"We followed the right procedures," Hobart told the Associated Press in a phone interview. "That plane had to depart. We wanted to get our customers to their destinations."

Oscar Munoz, CEO of United Airlines' parent company, described the event as "upsetting" and apologised for "having to re-accommodate these customers". He said the airline was conducting a review and reaching out to the passenger to "further address and resolve this situation".

When the manager approached the passenger, he said he was a doctor who needed to see patients in the morning, Bridges said.

Two officers tried to reason with the man before a third came aboard and pointed at the man "basically saying, 'Sir, you have to get off the plane'", Bridges said. That's when the altercation happened.

The four United employees then boarded the plane.

A few minutes later, the man who was removed from the plane returned, looking dazed and saying he had to get home, Bridges said. Officers followed him to the back of the plane.

Another man travelling with high school students stood up at that point and said they were getting off the plane, Bridges said.

About half of the passengers followed before United told everyone to get off, he said.

The man who was originally dragged down the aisle was removed from the plane again, and United employees made an announcement saying they had to "tidy up" the aircraft, Bridges said.

Bridges' wife told him she saw the man taken away on a stretcher, he said.

After a three-hour delay, the flight took off without the man aboard, Bridges said. A United employee apologised to passengers, he said.

- - With AP/PTI inputs