Chicago city council to grill United Airlines over bumping

In fresh developments regarding the passenger who was dragged off a United Airlines flight in Chicago, a city alderman said on Wednesday representatives from United Airlines and the city Aviation Department have been summoned by his committee to answer questions about the issue.

The passenger was dragged off a jet at O'Hare Airport.

Alderman Mike Zalewski says he does not know who will represent the airline before the city council's Aviation Committee. But the chief executive of United's parent company, Oscar Munoz, has been notified of the hearing scheduled for Thursday.

Chicago Aviation Commissioner Ginger Evans will also speak.

A video of the man being pulled from his seat after he refused to leave the full plane has been seen around the world and resulted in harsh criticism for United and Aviation Department police.

United Airlines CEO Oscar Munoz said earlier he felt "ashamed" watching the video of a passenger being dragged off a United Express flight and has promised to review the airline's passenger removal policy.

In an interview with ABC aired on Wednesday morning, Munoz apologized to Dr David Dao of Elizabethtown, Kentucky, his family and the other passengers who witnessed him being forcibly removed from the plane.

Munoz vowed this "will never happen again on a United flight" and that law enforcement won't be involved in future.

Munoz called the embarrassment a "system failure", saying United will review its policies for seeking volunteers to give up their seats when a flight is full. United was trying to find seats for four employees, which meant four passengers had to be deplaned.

Munoz defended the manner in which Dr Dao was treated before the video went viral, but subsequently, in his most contrite apology yet said on Tuesday that no one should be mistreated that way. He described the removal by airport police as "truly horrific". (See: United apologises over 'bumping' as even White House irate).

Munoz also said the company would reassess policies for seeking volunteers to give up their seats, for handling oversold flights and for partnering with airport authorities.

Meanwhile, details emerged about the passenger, who was identified as 69-year-old Kentucky physician David Dao.

The doctor was seen on cellphone videos recorded by other passengers at O'Hare Airport. He was convicted more than a decade ago of felony charges involving his prescribing of drugs and spent years trying to regain his license.