NEW YORK - The passenger who was violently removed from a U.S. plane is 69-year-old grandfather Dr David Dao, an American of Vietnamese origin, according to media reports.

Footage of the victim being dragged out of the overbooked United Airways flight at Chicago's O'Hare International Airport on Sunday caused outrage on Monday.

Dr Dao was heard in videos captured of his shocking eviction saying he needed to get home to Louisville so he could see patients.

He is  a father of five and a grandfather, who specializes in internal medicine. Four of his five children are doctors.

His wife Teresa, 69, is a pediatrician who trained at Ho Chi Minh University in Saigon and also practices in Elizabethtown, Kentucky -about 40 miles south of Louisville.

In the hours after his identity was revealed, United saw its stock price crash in morning trading action. The airline's share price hit a low of $68.39 at 11.13am, after opening the day at $70.15. It was a drop of about 2.6 per cent. But the price has recovered during the early afternoon, and is none back at $69.82, Market Watch reports.

It came after United CEO Oscar Munoz released a statement Monday night that doubled down on his airline crew's decision to remove an elderly passenger, claiming he was 'disruptive and belligerent'. The airline is facing a furious backlash after footage emerged of the 69-year-old, bleeding heavily as he was pulled from the jet.

Amidst the anger, Munoz issued a public apology saying he 'apologised for having to re-accommodate these customers.' But in a private email to employees, the CEO defended the crew's actions, calling the passenger 'disruptive and belligerent' and praising his staff for going 'above and beyond'.