(CBS) — About 25 protesters staged a rally outside of O’Hare International Airport’s Terminal One Tuesday evening over the forced removal of a passenger from a United Airlines flight.

Protesters said they were angered, appalled and outraged at the way Dr. David Dao was dragged off the plane when the airline tapped people who had to give up their seats to employees.

Protesters gathered at O’Hare airport Tuesday to condemn United Airlines over the forced removal of a passenger. (Bob Roberts/WBBM)

Some said United CEO Oscar Munoz should quit. Ahmed Rehab of the Council on American-Islamic Relations-Chicago said there were many ways to avert what happened to Dao.

“Airlines have to understand that they cannot act with impunity,” Rehab said.  “Policies have to change, customers have to be respected and minorities and everyone else as well.”

U.S. Rep.  Jan Schakowsky, D-Ill., said she wants congressional hearings and legislation that would bar airlines from removing passengers who are already seated aboard an aircraft.

Dao’s attorneys issued a statement Tuesday in which they said that he remains hospitalized.

Munoz earlier tried to cast blame on Dao for being belligerent, but on Tuesday he issued a statement accepting responsibility for what happened.