Serbian police deployed tear gas on Sunday to thwart hundreds of opposition supporters from entering the capital's city council building.
Despite the peaceful intent of the majority, some demonstrators hurled eggs at the government facility while protesting widespread vote irregularities in the recent general election.
The clashes unfolded after the Organization for Security and Co-operation in Europe (OSCE) cited "unjust conditions" and "misuse of public resources" during the vote. President Aleksandar Vucic dismissed these claims, labeling them as "lies" propagated by the political opposition, despite the European Union rebuking Serbia over electoral fraud reports and calling on the government to look into the claims.