Twenty Norwegian soldiers were slightly wounded on Wednesday, when 250 soldiers from the Norwegian KFOR unit in Kosovo became engaged in serious disturbances.
One man was killed when he tried to drive a car through a road-block south of the capital Pristina, and the Norwegian soldiers opened fire.
Two soldiers were slightly wounded when they were hit by the car.
The road block was put up in order to stop angry Albanians from reaching the Serbian village of Caglavica.
The UN has ordered a curfew in the province, following Wednesday's clashes in which at least 10 people were killed and 250 wounded.
The clashes between Albanians and Serbs began in Mitrovica, and threatened to spread.
The commander of the Norwegian KFOR unit says to NRK that his troops are prepared for the possibility of having to face further disturbances on Thursday.
At least one hand grenade also was thrown in the clash. Among the worst instances of Serb-Albanian bloodshed since the end of the Kosovo war in 1999, the violence starkly reflected the failure of UN and NATO efforts to replace ethnic hatreds with tolerance.
Initial reports by UN police spokeswoman Angela Joseph that a French peacekeeper had died of gunshot wounds were later denied by NATO and the French military.
Lt. Col. Jim Moran, a NATO spokesman, said a French and a Danish soldier were "seriously wounded," but reports that a peacekeeper had died were "completely not true."
Hospital personnel on the Serb and ethnic Albanian sides of divided Kosovska Mitrovica said four ethnic Albanians had died, apparently of gunshot wounds. Initial reports had said three Serbs were shot to death, but hospital personnel later revised that to two.
Capt. Athanasios Zormbas, a NATO spokesman, said 11 peacekeepers were injured.
Hospital employees on Kosovska Mitrovica's southern side, dominated by ethnic Albanians, counted more than 200 hurt, among them several who were shot. Xhelal Ibrahimi, an ethnic Albanian witness covered by the blood of a victim he carried to the hospital, said gunfire came from the Serb-dominated part of the town, and he saw several people falling in front of him.
On the Serb side, hospital physician Milan Ivanovic said 80 Serbs were wounded, including an unknown number shot; some were in critical condition.
In a separate hot spot, near Pristina, hundreds of ethnic Albanians broke through barricades erected by UN police and NATO-led peacekeepers to march on the Serb village of Caglavica. Joseph, the UN spokeswoman, said there were reports that hand grenades had been thrown and that two Serb houses were on fire.
Later, a town resident who spoke on the telephone but asked not to be named told The Associated Press that the situation had calmed down, with police separating Serbs and Albanians in the village centre.
But in a live radio broadcast from Caglavica heard in Belgrade, an unidentified witness said people were attacking each other with sticks and stones in village streets, amid the sound of explosions and gunfire.
In the western village of Belopolje, ethnic Albanians drove out Serb residents and set fire to their houses, said Joseph. And in Pec, 80 kilometres west of Pristina, ethnic Albanians had attacked the regional UN headquarters and damaged UN vehicles.
There was no immediate word on the injured in those confrontations.
The violence in Kosovska Mitrovica was the worst of its kind since February 2001, when ethnic Albanian terrorists blew up a bus carrying Serbs, killing 11 and injuring 40.
In other ethnic violence in the past year, three members of a Serb family were axed and clubbed to death in their home in the village of Obilic, their bodies then set on fire; a 43-year-old Serb died after being shot in the face while he was fishing near the village of Skulevo; and a hand grenade exploded in a shop in an ethnically mixed village in eastern Kosovo, killing one Serb man and injuring four others; and two Serb teenagers were shot to death while swimming in a lake.
The fact that most recent victims have been Serbs reflects how they have gone from Kosovo's Belgrade-backed rulers to a besieged minority, subject to attacks from members of the ethnic Albanian majority who continue exacting revenge for the 1999 Kosovo war.
In Kosovska Mitrovica, clashes similar to Wednesday's violence left nine people dead in 1999, shortly after the end of wholesale warfare between ethnic Albanians and Serbs.
Then, as now, the two sides squared off on opposite sides of the main bridge spanning the Ibar River and separating the two communities.
The hospital on the ethnic Albanian side of town was a scene of chaos Wednesday, with doctors urging people to give blood in crowded corridors. Their voices were occasionally drowned out by the cries of relatives looking for loved ones among the victims.
"I just felt pain and went down on the ground," said Ridvan Lahu, 41, who was shot in the stomach.
The bloodshed is a blow to the so-called "internationals," the UN and NATO officials running the province and struggling to get ethnic Albanians and minority Serbs to live together in peace.
The violence flared shortly after authorities recovered the bodies of two missing children from a river and just hours after reports that they were chased into the water by local Serbs. A third child remained missing. The three children were aged nine, 12 and 13.
The bodies were found after dozens of soldiers, police and civil emergency workers searched the Ibar River near the village of Cabra, some 40 kilometres north of the province's capital Pristina, said Joseph.
The search was launched after reports that three ethnic Albanian children had disappeared in the swirling waters Tuesday afternoon.
Fitim Veseli, 13, who said he was with the missing children, claimed they were being chased by local Serbs and the boys jumped into the river to escape a dog set on them by two Serbs from a neighbouring village. Veseli's nine-year-old brother, Florent, was among the them.
The drownings occurred a day after a 19-year-old Serb was shot and wounded in central Kosovo, in what Serbs blamed on unknown ethnic Albanian perpetrators.
Canadian peacekeepers are no longer posted in Kosovo; the majority in the region are stationed in Bosnia-Herzegovina. Less than half of the 40,000 NATO troops originally in Kosovo now remain, including about 2,000 Americans.
The Kosovo war ended in mid-1999 after a NATO air campaign drove Serb-dominated troops loyal to former Yugoslav president Slobodan Milosevic out of the province and stopped a crackdown on the independence-minded Kosovo Albanian majority. An estimated 10,000 people died in that war, most of them ethnic Albanians.
With Orthodox Christian Serbs regarding Kosovo as their ancient homeland and mostly Muslim ethnic Albanians seeking independence, hatreds between the two sides continue to boil over into violence, with each act of bloodshed leading to revenge from the other side.
The province itself is UN-administered but remains part of Serbia-Montenegro, the successor state to Yugoslavia, with its final status to be decided by the United Nations.