The US military is funding the research and development of a weapon that could be used to inflict excruciating pain from up to two kilometers away, but is meant to otherwise leave victims unharmed.

Intended for use against protesters and rioters, the research, reported by New Scientist magazine, focuses on the effect electromagnetic pulses can have on pain reception. Due to be ready by 2007, the Pulsed Energy Projectile (PEP) weapon will fire a burst of electrically charged gas, or plasma, which will generate an electromagnetic pulse on impact. It is this pulse that will trigger impulses in nerve cells causing extreme pain.

A review of the nonlethal weapon by the US Naval Studies Board in 2003 concluded that PEPs produced “pain and temporary paralysis” in animal test subjects. Studies ongoing at the University of Central Florida in Orlando aim to optimize this effect. The ultimate aim is to generate a pulse which will trigger optimum pain in a subject without damaging tissues.

Studies due to be carried out on lab grown cells aim at identifying the threshold of pain that can be inflicted on someone without causing death. There is some concern that the studies will fall short of demonstrating a safe level for a plasma burst.

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