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Serbia possesses sonic weapons but denies using them

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Russia's FSB investigating incident

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Experts say footage is inconclusive but suggests sonic

weapon

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President Vucic under pressure from street protests

By Aleksandar Vasovic and Milan Pavicic

BELGRADE, April 2 (Reuters) - Tamara Bojanovski was in a

crowd of anti-government protesters in Belgrade on March 15 when

she heard a sound "like some powerful machine hurtling up from

behind".

Thousands of others heard it too; the crowd packed into one

of the Serbian capital's main boulevards parted abruptly,

rushing to the sidewalks.

Stefan, a student, recalled a "rumble", then a "whoosh" and

a sensation of something speeding toward the crowd. Another

student, Dragica, felt "a wave travelling through us".

"People felt faint, and some fell over," said lawyer Bozo

Prelevic, a former joint interior minister.

The noise lasted only a few seconds.

But speculation that a sonic weapon was used illegally to

disperse the rally has filled headlines, talk shows and social

media. President Aleksandar Vucic, already facing the biggest

civil protests in decades, is under pressure to explain the

incident.

Sonic weapons employ extreme sound to incapacitate targets.

They can damage ears and cause headaches and nausea, and their

use is illegal in Serbia.

Authorities denied possessing such devices, until Interior

Minister Ivica Dacic admitted that police had bought Long-Range

Acoustic Devices - used by authorities in the United States,

Australia, Greece and Japan - from the U.S. in 2021.

Then Serbia's police, BIA security and intelligence agency

and military all denied ever using them in public.

Vucic said on Saturday that Russia had sent experts from its

FSB intelligence service to investigate at Belgrade's request,

and on Monday said American FBI investigators would also arrive

within days. The U.S. Department of Justice did not respond to a

request for comment.

The Omega Foundation, a human rights watchdog, said photos

and witness accounts they reviewed and audiovisual footage

obtained by Reuters were inconclusive, but suggested an LRAD

could have been used.

"We really haven't seen an effect like this. It was so

distinctive," said Omega Foundation researcher Neil Corney.

Earshot, a not-for-profit organisation that specialises in

audio investigations, which also saw the footage, said the noise

could have come from a vortex ring gun, an experimental

non-lethal weapon for crowd control that uses high-energy

doughnut-shaped vortices of air or gas, but that more research

was needed.

However, U.S.-based Genasys ( GNSS ), which makes LRADs, said that

audio and video evidence "does not support the use of an LRAD".

The protesters had gathered in memory of 15 people who died

when a train station roof collapsed in November in the city of

Novi Sad.

That tragedy, which many blame on government corruption and

shoddy construction, has drawn hundreds of thousands onto the

streets and forced prime minister Milos Vucevic to resign, as

well as continuing to put pressure on Vucic.

Geolocation of the videos suggests that the sound wave

travelled south along Kralja Milana Street for over 500 metres.

"The street emptied ... like when Moses parted the Red Sea,"

said Zoran Radovanovic, an epidemiologist who was in the crowd.