Please rotate your screen to portrait for optimal viewing experience

Chicago police said the man dragged off a United Airlines flight fell on an armrestby Circa News

UPDATE 3:24 p.m. EST:  An officer was placed on leave.

UPDATE 2:40 p.m. EST:  Chicago police released a statement saying the man fell. 

UPDATE 12:32 p.m. EST: United Airlines' CEO addressed the controversy.

An overbooked United Airlines flight led to a man being dragged off the plane after a computer chose to kick him off at random on Sunday.

The (Louisville) Courier-Journal reports United offered $400 and a hotel stay to get people to pick a different flight from Chicago to Louisville, then raised the offer to $800 when no one took the bait. Passengers were allowed to board in the meantime. Then a computer randomly selected four people to leave the plane. One couple left without incident, but another man refused to leave. Then security was called in.

Here's a video of the incident.

Here's another angle.

Audra D. Bridges told the Courier-Journal the man said he was a doctor who needed to see patients at a hospital that morning. The manager said security would be called if he did not leave willingly, and the man said he would call his lawyer. Eventually, a security officer threw him against the armrest and dragged him off the plane as he screamed.

The man was able to get back on the plane. He was disoriented and ran to the back of the plane. All other passengers were ordered off as a medical crew dealt with the dragged man.

"Everyone was shocked and appalled. There were several children on that flight as well that were very upset."

Audra D. Bridges, witness

The flight was delayed about two hours. Passengers were never updated on the man's condition.

United apologized for the incident in an email to the Courier-Journal, saying further questions on the man removed from the plane "should be directed to authorities."

United responded to the incident on Twitter, calling it "very concerning."

Some observers were outraged.

#DontFlyUnited trended on Twitter after the incident.

Others insisted the removal was justified.

The biggest technology failures in recent history