* Election two weeks ago halted by masked men
* Vote central to attempt to integrate Kosovo's Serb north
* Kosovo independence since 2008, not recognised by Serbia
NATO soldiers and EU police secured polling stations in the flashpoint Kosovo town of Mitrovica on Sunday for a re-run election central to a Western-sponsored plan to end the country's ethnic partition.
Masked men lobbing tear gas halted voting in Mitrovica two weeks ago, during a municipal election held for the first time in a northern, mainly Serb pocket of majority-Albanian Kosovo.
Ethnic Serb participation is central to an EU-brokered accord between Serbia and Kosovo aimed at integrating the mainly Serb north with the rest of Kosovo, more than five years since the former Serbian province declared independence.
The EU wants to see a peaceful and orderly vote that will elect a local council that will operate under Kosovo law, an outcome that local Serbs say will result in discrimination.
For years the north has functioned in a legal limbo, part of Kosovo but de facto under the control of Serbia in defiance of Kosovo's NATO and European Union overseers.
Serbia in April agreed to recognise Kosovo's legal authority over the north in exchange for accession talks with the EU, expected to begin in January.
Some 23,000 people, the vast majority of them Serbs, are eligible to vote on Sunday in the re-run, at three locations on the mainly Serb northern side of Mitrovica, a former mining town split largely between Serbs and Albanians since Kosovo's 1998-99 war.
Voters have been subjected to weeks of open intimidation by Serb hardliners trying to thwart the election, and intense pressure from Belgrade to take part and give legitimacy to the EU accord.
"I was called on Friday night and told that, as someone on welfare, they'd be giving out sugar, oil and a bit of money sent by the state so that I would vote for the government candidate," said Vesna Cosic, a pregnant unemployed Serb woman in north Mitrovica.
"Then they started to threaten. 'If you don't come on Sunday, we'll take you off welfare'," Cosic said. "I don't sell out for anyone, and certainly not for a few kilos of welfare."
Voting appeared to be very slow in the first hours after polls opened at 7 a.m. (0600 GMT). Besides NATO peacekeepers and armed EU police officers, dozens of so-called "civil protection" officers, part of an ad hoc public order force on the payroll of the Serbian state, milled around polling stations.
The directors of some state institutions and firms in north Mitrovica have openly called on their employees to vote.
"This kind of pressure wasn't even seen under (late Serb strongman Slobodan) Milosevic," said Oliver Ivanovic, a Mitrovica mayoral candidate running against Belgrade's favourite for the post, Krstimir Pantic.
Almost 15 years since NATO went to war to halt the killing and expulsion of Kosovo Albanians by Serbian forces during a two-year counter-insurgency war, the West is still trying to rein in the north.
Continued instability in the region has frustrated NATO's hopes of further cutting back its presence from the current 6,000 soldiers it has in Kosovo.
Serbia hopes that by resolving issues in the north, it can catch up with the likes of fellow former Yugoslav republic Croatia in joining the EU, driving reform and attracting investors to its struggling economy.
But the Mitrovica election has laid bare the depth of resistance among ethnic Serbs to integration with Kosovo's 90-percent Albanian majority, and the challenge facing the EU in implementing its accord.
"Pristina can't count on raising the Kosovo flag in the north. That won't happen," mayoral candidate Ivanovic told Reuters, flagging difficulties seen persisting whoever wins the vote.