Calls are mounting in Serbia for an independent investigation into reports that security forces used a sonic weapon on crowd at against a huge anti-corruption rally last weekend.

Serbian officials are denying that security forces illegally used a military-grade sonic weapon to disperse and scare protesters at a huge anti-government rally

Protesters had accused the police of using the outlawed device against crowds as hundreds of thousands gathered in Belgrade. The protests were described as the largest in Serbia's history.Serbia' s president Aleksandar Vucic has denied that his police forces used a banned' sonic weapon' to disperse protesters in Belgrade.