For more than two weeks, according to reports from media outlets close to the authorities, an investigation by unnamed inspectors of the Russian Federal Security Service (FSB) in Serbia into allegations that a so-called sound cannon was used at a rally in Belgrade on March 15th has been ongoing.
"Based on the results obtained, a categorical conclusion can be made that acoustic devices of the LRAD type that are in the possession of Serbian police authorities were not used during the protests," reads the report of the FSB expert group published on the website. Serbian Security Information Agency 16. April.
The BBC could not confirm the authenticity of the document, published in Russian and Serbian, without a date, memorandum or author.
"There are public indications of a staged provocation with the participation of a specially prepared group of people and the use of smartphones to synchronize movements while imitating the effect of an acoustic cannon and also blocking emergency services," the Russian investigators wrote in their conclusion.
The findings of a rare public report attributed to the FSB were read by Aleksandar Vučić, the president of Serbia, whose powers are largely ceremonial.
"The FSB is behind this, with its name and surname, with its signature," Vučić said, although it is not known who drafted the unsigned report.
Despite the alleged findings of the Russian service, it is still unknown who and how caused the separation of the crowd and panic at the protest on March 15th.
- A sudden break in the 15-minute silence during a protest in Belgrade, seen by a BBC journalist
- What does the Russian secret service say about the 'loud sound' at the protest in Belgrade on March 15th?
While protesters testified about an unexplained sound that sent them fleeing and in confusion, government representatives gave contradictory statements, denying that any sonic weapon had been used.
But none of the authorities have yet offered an answer to what people heard during the tribute to those killed in the November 1 canopy collapse in Novi Sad.
Non-governmental organizations, based on several thousand testimonies, addressed representatives of the United Nations and the European Court of Human Rights.
Students who have been protesting for months demanding responsibility for the deaths of 16 people in the collapse of a canopy at the Novi Sad train station have also added a demand for a thorough investigation into the incident at the protest on March 15th.
What does the FSB document say?
On three pages of text, often incomprehensible and narrowly specialized terms are used.
The first sentence states "establishing the circumstances of the movement of persons who participated in the memorial rally", which suggests a poor translation for the tribute and silence during which, according to many witnesses, an unexplained sound was heard.
By testing the technical characteristics of two types of LRAD sound devices on dogs, it was determined that the animals, called "biological objects", did not show any behavioral changes after being exposed to sound.
Audio and video recordings that, according to the report, were provided to Russian BIA agents from the scene – from surveillance cameras and mobile phones – were also analyzed.
The footage shows that "there are people in the crowd who are stirring up and orienting the crowd," directing the movement of the others from the front rows, it is stated.
There were also "several men in black hoodies setting some objects on fire in front of the ambulance," they added.
They determined that the "epicenter of the event was at the intersection of Dragoslava Jovanovića and Kralja Milana streets" near the National Assembly building, but also Pionirski Park, where a group of people presenting themselves as "Students Who Want to Learn" had gathered.
"In that place, a large number of aggressive people were concentrated who were following a certain scenario."
"Unexpectedly, they took off their yellow vests and headed in opposite directions, precisely in the direction of the Hotel Moskva and Slavija Square," which could be an allusion to the protest guards who immediately called for an end to the demonstration after the incident.
"In the video footage, there were no special cars or other special technical equipment, including large ones, at the aforementioned location."
"During the implementation of the action, riots began on the aforementioned street with the use of pyrotechnic and incendiary devices in front of an ambulance."
Later, there was a "synchronized lowering of hands with phones," with lights on them as a tribute to the 16 victims of the canopy collapse on November 1.
Vučić: Attempt at a colored revolution
On April 16, in one of his numerous addresses to the nation, Vučić read the findings and concluded what the document does not say - that this was an attempt at a "colored revolution."
"Everything was prepared for a violent takeover of power, including this news about the use of a sound cannon," Vučić said.
He mentioned the high-ranking German representative Manuel Zarazin, in charge of the Belgrade-Pristina dialogue, who stated that "the use of the sonic cannon does not contribute to Serbia's European path," adding that he had told a "notorious lie."
A color revolution is carried out through a pre-prepared attack on the state, Vučić claimed.
"A political, economic, psychological and informational war is being waged against Serbia."
He expects those responsible to be punished for misleading the public.
"Shame on you, you miserable liars, you wanted to do harm to your country," Vučić accused, without naming those he considers responsible.
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