Serbians living in northern Kosovo threatened violent opposition to the deployment, but the Kosovo officials and EU peacekeepers avoided confrontation with protesters.
Kosovar Prime Minister Hashim Thaci called the action a "successful start" to establishing law and order in the area even though it was widely opposed by the Serbians who make up most of the northern region's population.
Serbia does not accept the declaration of independence made by Kosovo's Albanian government in 2008. As a result, they say that Kosovo is still a part of Serbia, and so there is no justification for border controls.
Serbian Interior Minister Ivica Dacic warned earlier this week that the proposed action could lead to "new, heavy fighting" and the exodus of the 50,000 Serbs who live northern Kosovo.
But Mr. Dacic's dire predictions did not materialize. Serb protesters, including students from Belgrade, hung signs threatening to attack peacekeepers and erected a five-foot-tall barricade made of earth, bricks, and pallets. But the EU peacekeepers, who came by helicopter, were able to avoid confrontation with the protesters.