More than 3,000 people protested in Belgrade on May 10 against an EU-brokered deal to normalize ties between Belgrade and Kosovo, seen by ultra-nationalists as Serbia's tacit recognition of its former province's independence.
The protest was called by northern Kosovo Serb political leaders who, along with the ultra-nationalists in Serbia, have fiercely opposed the implementation of the deal.
Under the agreement, ethnic Serbs in northern Kosovo will have local autonomy and their own police force in exchange for recognizing the central government in Pristina.
Implementation of the agreement is an important precondition for Serbia opening accession talks with the European Union.
It is also crucial for Kosovo's signing of an association agreement with the European Union.
Serbia lost control over its former southern province in June 1999 after a NATO bombing campaign.
Based on reporting by AFP and RFE/RL's Balkan Service