On Friday, February 26, 1993, a violent explosion ripped through the sub-basement levels of New York's World Trade Center killing six people. The explosion and subsequent fire caused extensive structural damage in several basement levels, caused damage that interfered with the operation of the fire protection and other emergency systems, and resulted in the evacuation of approximately 100,000 occupants of the World Trade Center complex. Over 1,000 people were injured during the evacuation.
The World Trade Center complex includes seven high-rise buildings, a shopping mall and several levels of underground parking. The two largest high-rise buildings are 110 stories tall and are commonly referred to as the "Twin Towers". In addition to these high-rise buildings there is a 27-story high-rise building, a 21-story high-rise building (Vista Hotel), two nine-story high-rise buildings, and one eight-story high-rise building. Except for the 27-story high-rise building, all of the buildings are constructed over a plaza containing a 60-store shopping mall and four, underground levels of public parking.
A van containing explosives was parked on one of the underground parking levels in an area between one of the towers and the Vista Hotel. At 12:18 p.m., the explosives were detonated causing severe explosion-related damage on six levels of the complex. In the immediate area of the explosion, the floor slabs for two basement levels collapsed. The explosion also penetrated the floor for the Vista Hotel and combustion products spread immediately into the hotel lobby. Damaged windows between the hotel and one of the center's towers allowed smoke to quickly enter the tower lobby area. Elevators shafts that were damaged in the basement allowed smoke to spread into and fill the two towers, the Vista Hotel and another high-rise building in the complex.
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