According to authors Joe and Susan Trento, writing in 2006, the CIA places employees undercover with both airlines and the Federal Air Marshal Service, as a part of a program to allow known terrorists to keep flying (see May 2006). The undercover employees allow the CIA to control arrangements when it wants a terrorist to fly openly without the airlines’ or Marshal Service’s knowledge. [Trento and Trento, 2006, pp. 194] One example of this is travel in 2006 by Rayed Abdullah, an associate of alleged 9/11 pilot Hani Hanjour. Abdullah is allowed to fly to New Zealand for flight training in the hope he will meet al-Qaeda operatives, who will then be put under surveillance (see February-May 30, 2006).