NEW YORK, Nov. 28, 2016 /PRNewswire-USNewswire/ -- The following is being issued by Architects & Engineers for 9/11 Truth: The six-year investigation by the National Institute of Standards and Technology (NIST) into the fall of the World Trade Center Towers and nearby Building 7 on Sept. 11, 2001, which found that fires were to blame in all three collapses, was guided by a "pre-determined conclusion," said a former employee of the agency in a letter published last week in the European Physical Society's bimonthly magazine, Europhysics News. Peter Michael Ketcham, who, from 1997 until 2011, worked in NIST's High Performance Systems and Services Division and later in the Mathematical and Computational Sciences Division, described becoming furious as he read the agency's reports for the first time earlier this year. "The NIST I knew," he wrote, "was intellectually open, non-defensive, and willing to consider competing explanations. The more I investigated, the more apparent it became that NIST had reached a predetermined conclusion by ignoring, dismissing, and denying the evidence." Mr. Ketcham's rebuke of his former employer's study is the first time anyone with ties to the agency has challenged its conclusion that fires were the cause, although the agency's two reports have been the subject of intense debate since their release in 2005 and 2008, respectively. A contingent of engineers and other experts, along with a significant segment of the public, have long argued that the buildings' demise was caused by explosives and not by the airplane crashes. Europhysics News featured Mr. Ketcham's letter, as well as a statement from NIST, following the magazine's August publication of a controversial feature article by two engineers, a physicist, and a senior staff member of the organization Architects & Engineers for 9/11 Truth (AE911Truth). The article, " 15 years later: On the physics of high-rise building collapses," has been downloaded over 350,000 times, according to the website. Mr. Ketcham cited the widely read article as an example of the growing awareness of "the disconnect between the NIST WTC reports and logical reasoning." He ended his letter by calling on NIST to "blow the whistle on itself now while there is still time."