Thousands of protesters, mainly students, descended on Serbia's capital on Friday ahead of a planned weekend of massive anti-government rallies, many travelling hundreds of miles on foot or by bike.

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.