Jubilant crowds of ethnic Albanians celebrated on the streets of Kosovo today, waving red-and-black Albanian flags after the province's declaration of independence from Serbia.
The proclamation is the latest step in the bloody dissolution of Yugoslavia that began with the secession of Slovenia and Croatia 17 years ago.
In the ethnic Albanian section of the city of Mitrovica in northern Kosovo, ethnic Albanians chanted, danced and congratulated each other on the main square. Posters plastered on the town's walls thanked America and occasionally the European Union for their support.
"I have been waiting for this all my life," 39-year-old Flora Saciri, who took to the streets with her husband and two children, told ABC News. "This is such a big day for us."
"The most important thing is that we are free now," her husband said.
An impoverished and mostly Muslim province bordered by Serbia in the north and Albania in the Southwest, Kosovo has long been a point of conflict in the war-torn Balkan Peninsula.
Ethnic Albanians, who with nearly 2 million people make up 90 percent of Kosovo's population, have struggled for years to achieve independence from what they say is illegitimate Serbian rule.
But Serbians have for centuries considered Kosovo an integral part of their nation, and the government has cracked down on ethnic Albanian separatist movements in the past. Serbian leaders today denounced Kosovo's declaration of independence as a breach of international law.
In the Serbian capital of Belgrade, angry crowds sang patriotic songs and attacked the American Embassy with stones, breaking windows and stopping traffic in nearby streets.
The declaration of independence also pits Belgrade against the United States and the EU, which have long supported Kosovo Albanians' aspirations to self-rule.
In 1999, a U.S.-led NATO bombing campaign halted a Serbian attack on Albanian separatists. Since then, the province has been patrolled by 16,000 NATO-led peacekeepers and administered by U.N. and NATO officials.
In a televised address today, Serbian Prime Minister Vojislav Kostunica called an independent Kosovo "a false state" and accused the United States of propping up an unlawful regime, according to Reuters.
Belgrade's ally Russia was also quick to condemn the move and called on the United Nations to annul the declaration from Pristina, the capital of Kosovo.
"We expect the U.N. mission and NATO-led forces in Kosovo to take immediate action to carry out their mandate ... including the annulling of the decision of Pristina's self-governing organs and the taking of tough administrative measures against them," the Russian Foreign Ministry said in a statement.
"The decisions by the Kosovo leadership create the risk of an escalation of tension and inter-ethnic violence in the province and of new conflict in the Balkans," the Russian statement said.
But the United States was measured in its reaction.
"The United States is now reviewing this issue and discussing the matter with its European partners," State Department spokesman Sean McCormack said. "The United States will remain steadfast in its support for the rights of all ethnic and religious communities in Kosovo."
Straddling the winding Ibar River, Mitrovica embodies Kosovo's ancient divisions. Its population is made up of 50,000 Serbs, who live north of the river and use Serbian money, have Serbian license plates and read Serbian newspapers, and 80,000 ethnic Albanians, who stay south of the water.
After the declaration of independence Sunday, police closed the streets leading to the bridge linking the two halves of the town, with only journalists allowed into the north.
While the south celebrated, in northern Mitrovica the mood was calm but downtrodden. About 200 protesters gathered in the main square north of the river to oppose the province's declaration of independence.
"Kosovo is the heart of Serbia, and how can a man live without his heart," a Mitrovica Serb who declined to give his name told ABC News. "You will see that in five years Kosovo will be without any Serbs. Slowly everyone will leave."
Though official recognition from the EU is expected within two days, according to press reports, a newly independent Kosovo will likely lack formal recognition from the United Nations because of Russia's veto power on the Security Council.
And while their ethnic Albanian neighbors celebrated south of the river, in northern Mitrovica Serbs vowed loyalty to Belgrade.
Marko Jaksic, an orthopedic surgeon and Serb politician in Mitrovica, told ABC News on Saturday that Serbs' native "inat," meaning both stubbornness and spite, will ultimately return Kosovo to what he believes are its rightful rulers.
"This is the same 'inat' that had the Serbs reject the ultimatum of Austria-Hungary in July 1914, and the dictates of Hitler in April 1941," Jaksic said. "We have lived here for centuries. Why abandon our land, under the pretext that the Americans demand it?"
"The wind of history [will] eventually turn in our favor," he continued. "As always in the Balkans, whoever wins is the one who is able to show more patience. You see, one day we will return to Kosovo as a whole."