"Yeah. Hi. I'm on the 106th floor of the World Trade Center. We just had an explosion on the, on the like 105th floor," Hanley, 35, told an operator. Later, he says, 'We have smoke and ... it's pretty bad." An operator tells him to "sit tight. Do not leave, OK?"
Read the rest - http://www.cnn.com/2006/US/03/30/attacks.911.calls.ap.ap/index.html