During a massive protest in Serbia on March 15th, over 100,000 people gathered in Belgrade to protest government corruption. CCTV footage shows a sudden separation of the crowd near Terazije Square, with witnesses describing a loud noise resembling an airplane engine. Human rights groups accused Serbian authorities of using illegal Long Range Acoustic Devices (LRADs), but the government denies this.
Forensic audio experts, including Keith McElveen and Jim Foye of Wave Sciences, analyzed videos but found no evidence of an LRAD, though they noted that low infrasonic frequencies could have been lost due to compression. An NGO, Earshot, identified patterns in the audio more consistent with a vortex cannon, but no definitive proof of its use exists. The Serbian government insists no sonic weapons were deployed, yet thousands of protesters reported symptoms including nausea, headaches, and disorientation—common effects of acoustic weapons. The cause of the incident remains inconclusive. See here for more details.