sentences:  Placement of underwater or land-based communications cable taps, cameras, microphones, traffic sensors, monitors such as sniffers, and similar systems require that the mission go undetected and unsuspected.Clandestine sensors may also be on unmanned underwater vehicles, reconnaissance (spy) satellites (such as Misty), low-observability unmanned aerial vehicles (UAV), or unmanned detectors (as in Operation Igloo White and its successors), or hand-placed by clandestine human operations.The United States Department of Defense Dictionary of Military and Associated Terms (Joint Publication JP1-02, dated 5 January 2007) defines "clandestine operation" as "An operation sponsored or conducted by governmental departments or agencies in such a way as to assure secrecy or concealment.