Protesters burn U.S. Embassy in Serbia

The State Department's travel alert said the embassy's consular section would be closed Friday and Monday. It urged American citizens to avoid downtown Belgrade and said more protests could pose a danger. It said that U.S. citizens or family members concerned for the safety of U.S. citizens in Serbia can call 888-407-4747 toll free in the U.S. and Canada. Callers outside the U.S. and Canada were advised to use the regular toll line at 202-501-4444.

Kosovo, which is 90 percent ethnic Albanian, has not been under Belgrade's control since 1999, when NATO launched airstrikes to halt a Serbian crackdown on ethnic Albanian separatists. A U.N. mission has governed Kosovo since, with more than 16,000 NATO troops and KFOR, a multiethnic force, policing the province.

But Serbia — and Kosovo's Serbs, who make up less than 10 percent of Kosovo's population — refuse to give up Kosovo, a territory considered the ancient cradle of Serbs' state and religion.

Earlier Thursday, police estimated that about 150,000 people had attended a rally in the Serbian capital. The crowd waved Serbian flags and carried signs reading "Stop USA terror." One group set fire to a red-and-black Albanian flag.

Those involved in the attack on the U.S. embassy were mainly young men, some of whom wore balaclavas and scarves to hide their faces. They had attacked the building with sticks and metal bars and destroyed two guard boxes outside.

Protesters ripped some metal grilles from the embassy windows and also tore a handrail off the building's entrance and used it as a battering ram against the main door.

Unrest in Kosovo
There also has been unrest in Kosovo since the independence declaration. Hundreds of Serbs have launched attacks on border outposts, prompting NATO to reinforce the northern Serb-dominated part of Kosovo and take control of the borders.

The violence has sparked fears of sustained violence, with Serbian officials saying the attacks were in line with its attempt to contest Kosovo's secession.

Ethnic Albanian separatists fought a 1998-99 war with Serbian forces, and an estimated 10,000 people were killed.

In areas of Kosovo where Serbs live surrounded by majority ethnic Albanians, Serb leaders urged Serbia's government to tone down statements or risk endangering lives.

"Serbs from the north have brought other Serbs in Kosovo in a position to fear for their children and their lives, which is a very painful feeling — the fear of what your own people might do," Kosovo Serb leader Rada Trajkovic was quoted Thursday as saying by the independent Serbian news agency FoNet.

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