A document obtained and witnesses interviewed by Fox News raise new questions over whether there was an effort by the Defense Department to cover up a pre-9/11 military intelligence program known as Able Danger." At least five witnesses questioned by the Defense Department's Inspector General told Fox News that their statements were distorted by investigators in the final IG's report -- or it left out key information, backing up assertions that lead hijacker Mohammed Atta was identified a year before 9/11. Lt. Col Tony Shaffer, an operative involved with Able Danger [and author of Operation Dark Heart, a recent book which discussed the Able Danger operation, and all copies of which were destroyed by the Pentagon] said, "My last interview was very, very hostile." When asked why the IG's report was so aggressive in its denials of his claims and those of other witnesses -- that the data mining project had identified Atta as a threat to the U.S. before 9/11 -- Shaffer said [the] Defense Department was worried about taking some of the blame for 9/11. Specifically, the Defense Intelligence Agency ... wanted the removal of references to a meeting between Shaffer and the executive director of the 9/11 Commission, Philip Zelikow, removed. Shaffer alleges that in that meeting, which took place in Afghanistan, the commission was told about Able Danger and the identification of Atta before the attacks. Shaffer, who was undercover at the time, said there was "stunned silence" at the meeting. No mention of this was made in the final 9/11 Commission report.