KOSOVSKA MITROVICA, Kosovo -- Violent protests rocked Serb-dominated northern Kosovo yesterday, as mobs chanting "Kosovo is ours!" hurled stones, bottles and firecrackers at U.N. officers guarding a bridge that divides Serbs from ethnic Albanians.

The scenes evoked memories of the carnage unleashed by former Serb autocrat Slobodan Milosevic the most recent time that Kosovo tried to break away from Serbia, which considers the territory its ancestral homeland.

There were disturbing signs that the riots in Belgrade, Serbia, and in Mitrovica have the blessing of nationalists in the Serbian government, which hopes to undo the loss of the beloved province.

Prime Minister Vojislav Kostunica's authorities repeatedly have vowed to reclaim the land, despite U.S. and other Western recognition of Kosovo's statehood. Some hard-line government ministers have praised the violent protests as "legitimate" and in line with government policies of retaining control over Serb-populated areas.

Serbian President Boris Tadic called an emergency meeting of the national-security council and said the rioting that engulfed the capital must "never happen again."

"There is no excuse for the violence," Tqadic said. "Nobody can justify what happened yesterday."

Tadic and Kostunica differ sharply on Kosovo, with Tadic saying that Belgrade must press on with efforts to join the EU regardless of Kosovo. Kostunica wants to drop the bid because most EU countries plan to recognize the province's independence.

Kostunica appealed for an end to the violence. "This directly damages our ... national interests. All those who support the fake state of Kosovo are rejoicing at the sight of violence in Belgrade."

Kosovo's ethnic-Albanian leaders declared independence from Serbia on Sunday. The province, which is 90-percent ethnic Albanian, has not been under Serbia's control since 1999, when NATO airstrikes halted a Serbian crackdown on ethnic-Albanian separatists. A U.N. mission has governed Kosovo since.

The U.S. ambassador to Serbia demanded that authorities do more to guarantee the safety of foreign diplomatic missions after nationalists in Belgrade set fire to the U.S. Embassy during riots Thursday that left one person dead and more than 150 injured.

The State Department ordered nonessential diplomats and families of American personnel at the embassy to leave Serbia after the attack.

In his first post-independence interview, Kosovo's prime minister said: "The pictures of yesterday in Belgrade were pictures of Milosevic's time."

Yesterday in Kosovska Mitrovica, about 5,000 Serbs rallied during a fifth day of protests since the independence declaration. Protesters lobbed firecrackers in a skirmish with police. The clashes took place on a bridge over the Ibar River, long a flashpoint of tensions.