Jerusalem, June 4 (AP): The Israeli army has unveiled a new crowd-dispersal tactic, emitting painful bursts of sound at a special frequency to help break up a violent Palestinian demonstration, military officials and witnesses said.

Israeli military officials confirmed soldiers used a new “non-lethal” tactic yesterday in the West Bank village of Bilin, where hundreds of demonstrators rallied against Israel’s separation barrier.

The officials, speaking on condition of anonymity under army regulations, said the weapon uses “voice frequencies” to disperse crowds.

It took Israel four years to develop the technology.

An AP photographer said a military vehicle arrived toward the end of the demonstration. Located about 500 metres from the demonstration, the vehicle emitted several bursts of sounds, about one minute in length each time.

Although the sound was not loud, it caused people to cover their ears and grab their heads in discomfort.