Frantic conversations between trapped people and authorities during the moments before the World Trade Center towers collapsed on September 11, 2001, are revealed in transcripts of radio and telephone transmissions and in handwritten notes that were released Thursday.
"Which stairs do we take?" asked one man working in the 78th floor of the North Tower, WTC 1, the first building attacked at 8:46 a.m. when a hijacked Boeing 767 hit it between the 93rd and 98th floors.