It was one of the most shocking events of modern times; an attack on an a scale previously unimaginable, and a day that should never be forgotten.
Using contemporary accounts, the stories of witnesses and survivors, and the words of the victims, I'll tell the story of 9/11.
This is a series in six parts. This episode looks specifically at the hijacking of United Airlines Flight 175, and events at the South Tower of the World Trade Center.
Visit www.greatdisasters.co.uk for the full transcript and more.
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