http://www.youtube.com/watch?v=79o9fFwTStc

"A group of experts and professionals called architects and engineers for 9/11 truth, led by architect Richard Gage, has come to Washington D.C. to present contrary scientific evidence to the U.S. government's explanation that the three WTC towers collapsed due to fires. According to Gage and hundreds of other experts, a controlled demolition involving explosives had taken place; therefore, volunteers came from all over the country to encourage other Americans to demand a new investigation into the September 11th terrorist attacks."