There's been a growing movement led by some architects and engineers to take a second look at the collapse of the New York City skyscrapers in the attacks on September 11th 2001. Architects and Engineers for 9/11 Truth" focuses primarily on Building 7 of the World Trade Center. Not many people know that a third building fell on 9/11. Tony Szamboti is a mechanical engineer from Blackwood, New Jersey. He says the 47 story skyscraper was not hit by a planeyet collapsed into its own footprint at 5:20 in the afternoon. "It's in absolute freefall. There's no resistance to it for the first 2.25 seconds and then it slows down a little bit," Szambotti said. "The actual measurements are somewhere around 6.6 to 7 seconds for that 610 foot building to collapse completely to the ground." Szamboti and some 2,000 [of] his colleagues contend that it was not scientifically possible for an office fire to be hot enough to melt steel girders and columns. Which brings these highly educated, white-collar professionals to a disturbing conclusion. "We believe there were pre-planted charges in the building." The group doesn't speculate as to who may have planted charges, but it's launching a new campaign today to spur a new investigation. "We would like, whoever had access to those buildings to be investigated and that has never been done." "Rethink 9/11" features a daylong rally beneath a new billboard in Times Square and 11 other cities to drum up support for the investigation.