What it is
The sound cannon is the common name for the disputed question of whether a sonic weapon, including LRAD, was used during Belgrade's student protest on 15 March 2025. It is not a court-established fact: state bodies denied use of a device, while some participants and independent organisations said the opposite.
Why it became important
During 15 minutes of silence for the victims of the Novi Sad canopy collapse, people in Ulica kralja Milana suddenly split apart; many later reported dizziness, nausea, headaches and tinnitus. The public dispute intensified after reports that police possessed LRAD 450XL devices and became part of a broader argument over state conduct at the protest.
What VJT is examining
On 19 June 2026, Belgrade's Higher Public Prosecutor's Office (VJT) said it had asked UKP's counter-terrorism service to gather information about documents temporarily seized during a 27 March search of the Faculty of Philosophy. In the prosecution's account, the documents may point to preparation of a simulated sound-cannon use on 15 March. It also asked for people at the meeting mentioned in the documents to be identified and for people who publicly alleged device use to be interviewed.
Latest known episode
On 1 August, Danas carried an Eko straža statement saying its founder Bojan Simišić was held at the border after a work trip, gave a statement as a citizen to UKP's counter-terrorism officers, and was then released; the organisation said his phone was not taken. Eko straža links the interview to the sound-cannon case. The available report contains no separate UKP or VJT comment on why Simišić was questioned.
Current status
As of 5 August 2026, the public record shows information gathering and interviews to gather information, not an indictment or court ruling. Neither the alleged use of LRAD on 15 March nor the account of a planned simulation has been established in court. For now, the competing claims remain the parties’ respective positions, until prosecutors announce a procedural decision and its grounds.
Why it matters
The case affects protesters, witnesses, medical staff and people asked to give explanations. It also bears on trust in the investigation of 15 March and on whether the competing accounts of the panic in Ulica kralja Milana can be independently examined.
Open question
The next key question is whether VJT will publish the documents it is examining and say what procedural decision followed the information gathering. It is still unclear whether the inquiry will become a specific criminal case and what material will be available for independent assessment.