In honor of the people who died during the Sept. 11, 2001, terrorist attacks on the United States, the Washington Fire Department displayed a flag over East Washington Street from its ladder truck. At the front of the ladder truck an empty firefighter?s uniform is displayed in honor of the firefighters who died attempting to rescue people. The series of four coordinated attacks on the United States killed 2,996 people and injured over 6,000 others. During the attacks terrorists flew hijacked jet airliners into the two World Trade Center towers, causing them to collapse. A third airliner was flown into the Pentagon building. A fourth crashed in a field in Pennsylvania.