* Serbia urging Serbs in north Kosovo to vote for first time
* Hardliners waging campaign for boycott
* Vote part of EU-brokered accord between Balkan neighbours
Widespread intimidation in a volatile Serb pocket of Kosovo marred a watershed election on Sunday, part of a European Union-brokered rapprochement between the Balkan country and its former master Serbia.
The Kosovo-wide council and mayoral elections are central to an agreement reached in April to integrate Serb-populated northern Kosovo with the rest of the country, which is majority Albanian and declared independence from Serbia in 2008.
Serbia has called on Serbs in north Kosovo to take part for the first time, hoping it will smooth Belgrade's path to EU membership talks expected to begin in January. But Serb hardliners in northern Kosovo, who reject Kosovo's secession, have waged a sometimes violent campaign for a boycott.
"These elections are an act of high treason that will ultimately cut Kosovo off from Serbia and lead to a Serb exodus from Kosovo," said 22-year-old student Negovan Todorovic. "Belgrade is betraying Kosovo for the vague prospect of the so-called benefits of so-called European integration."
Krstimir Pantic, a Belgrade-backed candidate for mayor in the Kosovo Serb stronghold of Mitrovica, was attacked on the street by two masked men late on Friday, suffering cuts and bruises to his face.
Pantic was cursed by dozens of Serbs wearing badges that read "Boycott 100 percent" as he entered a polling station to vote, where two out of four members of the voting commission had failed to turn up.
The municipal election is the most tangible sign so far in the shift in official Serbian policy towards its former southern province.
Serbia lost control of Kosovo in 1999, when NATO bombed for 11 weeks to halt the killing and expulsion of Albanians by Serbian forces trying to crush a guerrilla insurgency.
Belgrade retained de facto control over a small pocket of the north, where some 40,000-50,000 Serbs live largely beyond the reach of the Kosovo authorities. Serbia, however, agreed to cede the foothold in April in exchange for EU accession talks that the former Yugoslav republic hopes will help lure investors to its struggling economy.
Preliminary election results are expected on Sunday evening but are unlikely to bring about much change at the state level. Turnout among Serbs in the north will give an indication of the scale of resistance to integration with the rest of Kosovo and the challenge facing councillors and mayors who will take up office.
Milka, a 43-year-old Serb woman who refused to give her full name, said she would not vote for fear of losing her job in a state-run company where the manager is in favour of a boycott.
"For days he has been threatening us he will personally visit all polling stations and whoever he sees voting will be sacked," she said.
Nationalist hardliners had also travelled south from Serbia to back the boycott.
"I came here with dozens of my brothers to prevent this shameful sale of Serbian soil," said a man who gave his name as Stevica. "We'll go to the polling stations to see who are the traitors, cowards and scum of the earth who want to betray Serbia."
Others said they would not be deterred.
"I've been living here for almost 80 years and I came to vote because if we do not take part in elections, Serbs will vanish from Kosovo," said 79-year-old pensioner Milorad Stijovic. "These people, the boycotters, cannot intimidate me. I'm too old and I've seen worse than them."