http://www.groupintel.com/2011/04/11/the-projected-al-qaeda-use-of-body-cavity-suicide-bombs-against-high-value-targets/
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Ultimately, however, it is going to require some sort of reliable and medically safe form of body cavity imaging of human beings, in addition to exterior body scans, that is quick enough to make it economically feasible in airport security settings with their potentially long passenger ques. Until the future fielding of such advanced scanning devices, we can now expect to be attacked individually, and just as likely attacked in clusters, by Al Qaeda operatives carrying body cavity suicide bombs inside of themselves on commercial airliners.http://www.groupintel.com/wp-content/uploads/2011/04/Bunker-GroupIntel_BodyCavityBombs.pdf