U.N. police in Kosovo fired teargas and rubber bullets during clashes yesterday with ethnic Albanians protesting against a U plan on the fate of the breakaway Serbian province.
Hospital officials said they had treated 70 people, including four who were seriously wounded.
Reuters reporters saw dozens of people arrested as Kosovo Albanian and UN riot police advanced on hundreds of demonstrators who were hurling stones and bottles.
The clashes, a repeat of riots in November, underscored Western fears of what the United States described last week as a possible "breakdown in order" if a decision on the Albanian majority's demand for independence does not come soon.
A UN plan unveiled this month would, if adopted by the UN Security Council, set the territory on the path to statehood, eight years after NATO bombs drove out Serb forces and the United Nations took control.
But some among Kosovo's 90-perc ent ethnic Albanian majority are angry at the plan's provisions for a powerful European overseer and self-government for the 100,000 remaining Serbs.
The protesters, dismissed by Kosovo's leaders as fringe elements, called for a referendum on independence and rejected negotiations with Serbia, which in 1998-99 killed 10,000 Albanians and expelled 800,000 in a two-year war with rebels.
Serbia opposes the amputation of its medieval heartland, but the Albanians living there reject any return to Serb rule and are impatient to end eight years of UN-imposed limbo.
Washington and the European Union back Ahtisaari's blueprint and hope the UN Security Council will adopt it by June.
UN veto holder Russia, however, repeated yeterday that it would only back a solution that was also acceptable to fellow-Orthodox nation Serbia.
Ahtisaari has invited Serbia and the Kosovo Albanians to a final round of talks in Vienna from February 21 and hopes to present the plan to the UN Security Council in late March.
The West has already delayed the process twice to avoid radicalising Serbia.
Ahtisaari said on Friday he saw no chance of the two sides agreeing, "even if I negotiated all my life".
Earlier yesterday, Kosovo President Fatmir Sejdiu and Prime Minister Agim Ceku paid a rare visit to the mainly Serb north of the province for a security briefing by commanders of the 16,500-strong NATO peace force in Kosovo.
The strip of land above the River Ibar has been off-limits to Kosovo Albanian leaders since the war.
Some Serbs there have threatened a breakaway bid if Kosovo wins independence.