LONDON -- A sonic weapon used to ward off pirates attacks and drive back rioting crowds will be part of the security arsenal at the London Olympics, Sky News reported Saturday.
The American-built long-range acoustic device (LRad) can emit a highly focused beam of sound at a pain-inducing 150 decibels (dB), louder than the takeoff of military jets and just below the instant perforation of an eardrum.
The US army deployed LRad as a crowd control device during its struggles in post-war Iraq.
More recently, it used a vehicle-mounted system against G20 protesters in Pittsburgh in 2009, driving back demonstrators with the LRad's high-pitched sound.
The devices also were being used on cruise liners to combat the threat of pirates in the Indian Ocean.
Britain's Ministry of Defence confirmed that LRad was among a "broad range of assets" being used by the armed forces to provide security during the summer's Games.
A spokesman said it would be used primarily in its high-powered "loud hailer mode," rather than to deliver the ear-piercing beams of sound, to issue warnings to any boats on the River Thames that were causing concern.
Some models are now "man portable" backpacks that can blast alarm warnings at 137 dB, and can be used as land-based loud hailers with a range of 0.6 miles.