NATO-led peacekeepers have confronted crowds of angry Serbs as they moved into Kosovo's northern border area to try to remove a series of roadblocks that has been in place for almost three months.

Peacekeepers in full riot gear moved into the area near Zubin Potok Thursday, accompanied by armored vehicles, trucks and bulldozers. NATO says it took down some of the 16 roadblocks on the roads leading to two disputed border crossings. Hundreds of Serbs had come out to keep the peacekeepers from dismantling the roadblocks, but the NATO-led forces fired tear gas in an attempt to break up the crowd.

Officials say more than a dozen Serbs were treated for minor injuries and the effects of tear gas, while eight peacekeepers were also slightly hurt.

Thursday's confrontation comes one day after Serb leaders met and refused NATO's request to remove the barricades and allow free movement in the area. In Belgrade, Serb President Boris Tadic encouraged the Kosovo Serbs to protest peacefully and asked peacekeepers to refrain from violence.

Kosovo Prime Minister Hashim Thaci called on citizens in northern Kosovo to remain calm and fully cooperate. He blamed the confrontations on criminals in the north.

Kosovo Serbs put up the barricades after Kosovo's ethnic Albanian-dominated government tried to take control of the border crossings in July as part of a trade dispute. An attempt by Kosovo police to take down the barricades erupted in violence, resulting in the death of an ethnic Albanian police officer.

About 40,000 Serbs live in northern Kosovo, making up the majority in a number of towns. They refuse to recognize the authority of the government in Pristina, which unilaterally declared independence from Serbia in 2008.

Belgrade has urged Kosovo Serbs to find a compromise to the crisis, after the European Union made it clear Serbia cannot be considered for entry into the EU this year unless the situation in Kosovo improves.