The Army's main CREW system is the Warlock Duke, a vehicle- mounted radio jammer developed by Syracuse Research Corporation.

CNN: Jamming systems play secret role in Iraq

It is widely reported a radio jammer inside the car of Pakistani President Pervez Musharraf stopped an attempt to assassinate him last December.

CNN: Mobiles used in high-tech terror

In trials conducted by the General Lighthouse Authorities of UK and Ireland, a 1.5W radio jammer was able to knock out GPS signals over a range of 30 kilometers.

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