On September 11, 2001, terrorists hijacked four passenger aircraft and turned them into missiles in attacks on the United States that killed almost 3,000 innocent people. American Airlines Flight 11 and United Airlines Flight 175 struck the World Trade Center in N.Y.C., American Airlines Flight 77 hit the Pentagon in Washington, D.C., and United Airlines Flight 93 crashed at Shanksville, PA. Described as the most horrific peacetime assault in the country's history, the attacks killed defenseless civilians, including fathers, mothers, sisters, brothers, and grandparents. The nation came together in mourning, and every state sent aid to the three attacked sites. Brave men and women of the N.Y.C. Fire Dept., N.Y.C. Police Dept., and other uniformed emergency service responders faced extreme danger to save thousands of citizens and foreign visitors.