NATO troops on guard in north Kosovo for third day amid protests

LEPOSAVIC, Kosovo, May 31 (Reuters) - NATO peacekeepers guarded town halls in ethnically polarised north Kosovo for a third day on Wednesday as Serbia's defence minister inspected troops deployed near the border with its former province after violent unrest this week.

The disturbances prompted NATO to send additional troops to the area and the alliance and the West slammed Kosovo for not having done enough to prevent violence, during which 30 NATO troops and 52 ethnic Serb protesters were hurt on Monday.

NATO said it would send 700 more troops to boost its 4,000-strong mission in Kosovo, where Serbs are angry that a 2013 deal to set up an association of autonomous municipalities where they form a majority in the north has never been implemented.

Regional unrest has intensified since April elections that Serbs in north Kosovo boycotted, leaving victory in four Serb-majority mayoralties to candidates from Kosovo's 90% ethnic Albanian majority.

After they were installed last week despite a 3.5% election turnout, the U.S., the most outspoken supporter of Kosovo's 2008 independence from Serbia, decided to cancel Pristina's participation in a NATO military exercise.

U.S. Ambassador to Serbia Christopher Hill said on Wednesday there might be additional moves but declined to elaborate.

"We want more progress in Kosovo, we want the establishment of the association of Serb municipalities, we want the normalisation of undertakings (pledged) by both countries including by Serbia," Hill told reporters in Belgrade.

Kosovo media reported on Wednesday that protesters outside a town hall in Zvecan, who were separated from Polish NATO troops by a razor-wire barrier, had broken windows on a police car and two cars belonging to Kosovo Albanian media outlets.

Northern flashpoint towns were largely calm on Wednesday.

NATO soldiers also stood guard outside a municipal hall in Leposavic where its ethnic Albanian mayor remained holed up after entering it amid Serb protests on Monday.

"While (these mayors) may have been legally elected, we do not consider their election legitimate," Dragan, an ethnic Serb who lives in Leposavic and declined to give his last name, said on Wednesday.

Serbian Defence Minister Milos Vucevic visited a military base in Raska, near the border with Kosovo, and inspected soldiers with tanks lined up behind them after President Aleksandar Vucic put the country's army on full combat alert.

Vucevic said he wanted peace and stability "but without compromising our ability to defend the sovereignty of the Republic of Serbia and all of its citizens" - alluding also to Kosovo Serbs who do not recognise Kosovo statehood.

The United States, NATO and allies have rebuked Kosovo's government for stoking tension with Serbia, saying that forcefully installing the mayors in ethnic Serb areas undermined efforts to achieving lasting peace in the region.

Kosovo Prime Minister Albin Kurti accused Belgrade of orchestrating protests in the north to destabilise Kosovo, which secured statehood a decade after a guerrilla uprising against repressive Serbian rule.

Separately, Kosovo Olympic authorities asked the International Olympic Committee to open disciplinary proceedings against Serbian tennis star Novak Djokovic, accusing him of stirring political tension with remarks made at the French Open.

Djokovic wrote "Kosovo is the heart of Serbia" on a camera lens on Monday, the day NATO troops and Serbs were hurt in clashes in Zvecan, where his father grew up.