linguistic:paraphrasing
September 11 attacks

On September 11, 2001, coincidentally the 60th anniversary of the Pentagon's start of construction, five al-Qaeda affiliated hijackers took control of American Airlines Flight 77, en route from Washington Dulles International Airport to Los Angeles International Airport, and deliberately crashed the Boeing 757 airliner into the western side of the Pentagon at 9:37 am EDT as part of the September 11 attacks. The impact of the plane severely damaged the outer ring of one wing of the building and caused its partial collapse. At the time of the attacks, the Pentagon was under renovation and many offices were unoccupied, resulting in fewer casualties. Due to the renovation work, only 800 people were there, as opposed to the usual 4,500. Furthermore, the area hit, on the side of the Heliport façade, was the section best prepared for such an attack. The renovation there, improvements which resulted from the Oklahoma City bombing, had nearly been completed.