Croatia is expected to vote for EU membership on Sunday, to the dismay of nationalists who protested in Zagreb on the eve of the referendum.
The demonstration turned ugly and several arrests were made.
Right-wing activists and war veterans are among the anti-EU lobby in a country that has long remained on the sidelines of Europe.
Protesters’ efforts to remove the EU flag ended in clashes with police.
While some fear a loss of sovereignty, Croatia’s government sees EU membership as an opportunity, with the country hit hard by the economic crisis.
Foreign Minister Vesna Pusic also took to the streets, to campaign for a ‘yes’ vote. Opinion polls suggest EU entry will get the green light, with up to 60 per cent support.