The rally on Saturday in the capital, Belgrade, came as protests have spread to towns around the country and have drawn increasingly insistent calls that President Aleksandar Vucic step aside.

The rally was part of a nationwide anti-corruption movement that erupted after a concrete canopy collapsed at a train station in Serbia's north in November, killing 15 people.

Large crowds of flag-waving protesters converged after meeting up at several agreed-on protest venues in various parts of Belgrade, which was placed on high alert.