D.C. Del. Eleanor Holmes Norton (D) wants a congressional hearing into an incident in which a man was dragged off a United flight by uniformed security officers after he refused to give up his seat.

The incident, which happened at Chicago’s O’Hare International Airport on Sunday, has drawn outrage from members of the public, prompting United’s CEO Oscar Munoz to issue an apology.

A spokeswoman for the Chicago Department of Aviation said in a statement on Monday that one of the officers allegedly involved in the incident has been suspended.

Norton called the incident an outrage.

“I deplore the violent removal of a passenger from a United Airlines flight this weekend,” she said in a statement. “Airline passengers must have protections against such abusive treatment.  I am asking our committee for a hearing, which will allow us to question airport police, United Airlines personnel, and airport officials, among others, about whether appropriate procedures were in place in Chicago and are in place across the United States when passengers are asked to leave a flight.”

Norton was referring to the House Transportation and Infrastructure Committee.

She said on Tuesday that she will release a letter she sent to the committee’s chairman, Rep. Bill Shuster (R-Pa.), and Rep. Frank LoBiondo (R-N.J.), chairman of the aviation subcommittee, requesting a committee hearing to examine this and other incidents on flights.

Late last month, United was under fire after a traveler at Denver International Airport tweeted that two teenage girls were being barred from a United flight because they were wearing leggings. In the end, it turned out the girls were flying on company travel passes, which require travelers to follow the airline’s dress code. Still, some criticized the policy as dated and discriminatory against women. And, it became a public relations nightmare for the airline.