Minnesota State Patrol uses long range acoustic device, first used by military, to disperse Maple Grove protesters

Minnesota State Patrol troopers used a powerful sound system first used by the military in Maple Grove, Minnesota, to ...
Northcountrypublicradio.org

Focused Sound 'Laser' for Crowd Control

Several police departments across America are planning to try a new device that uses focused sound, turned way up. These so-called non-lethal... Focused Sound 'Laser' for Crowd Control Crowd control ...