Protesters in Serbia who staged one of the country’s biggest-ever rallies claim the authorities used a prohibited, military-grade sonic weapon to disperse peaceful crowds.

Calls were mounting in Belgrade on Monday night for an independent inquiry into claims that security forces deployed the device during the anti-government, anti-corruption demonstration that was held in the capital on Saturday, drawing about 300,000 people.

Video footage posted on social media showed thousands of people standing in the streets during a 15-minute silence to remember the victims of a railway station roof collapse, which happened in the city of Novi Sad in November.

The tragedy, which claimed the lives of 15 people, sparked months of protests against President Vucic and his nationalist government, shaking his decade-long grip on power.