Hundreds of ethnic Serbs on Wednesday gathered in a town in northern Kosovo, days after clashes that injured 30 soldiers from a NATO-led peacekeeping force and over 50 Serbs, provoking fears of a renewal of the region's bloody conflicts and prompting the Western military alliance to send in additional troops. The Serbs reiterated that they want the Kosovo special police and ethnic Albanian officials they call "fake" mayors to withdraw from northern Kosovo. The crowd then spread a huge Serbian flag. Wednesday's protest outside the city hall in Zvecan, 45 kilometers (28 miles) north of the capital, Pristina, was peaceful as of late morning. On Monday, ethnic Serbs tried to storm municipal offices and fought with both Kosovo police and the peacekeepers. Serbs are a minority in Kosovo, but a majority in parts of the country's north bordering Serbia. Many reject the Albanian-majority territory's claim of independence from Serbia. A former province of Serbia, Kosovo's 2008 declaration of independence is also not recognized by Belgrade. The United States and the European Union recently have stepped up efforts to solve the dispute as the war rages in Ukraine. NATO said it will send 700 more troops to northern Kosovo to help quell violent protests after the clashes on Monday. The NATO-led peacekeeping mission, KFOR, currently consists of almost 3,800 troops. U.S. Secretary of State Antony Blinken urged "all parties to take immediate actions to de-escalate tensions." Blinken described violence against soldiers from the multinational force known as KFOR as "unacceptable." The confrontation first unfolded last week after ethnic Albanian officials, who were elected in a vote that Serbs overwhelmingly boycotted, entered municipal buildings to take office with an escort of Kosovo police. When Serbs tried to block the officials, Kosovo police fired tear gas to disperse them. In Zvecan on Monday, angry Serbs again clashed first with the police and later with NATO-led troops who tried to secure the area. Serbia put the country's military on its highest state of alert and sent more troops to the border with Kosovo. While Washington and most EU nations recognize Kosovo's statehood, Belgrade has the backing of Russia and China in rejecting it. Western officials have sharply criticized both Kosovo's authorities for pushing to install the newly-elected mayors, and Serbs because of the violence. "The Government of Kosovo's decision to force access to municipal buildings sharply and unnecessarily escalated tensions," said Blinken. He urged Kosovo to use alternate locations for the new mayors and withdraw police from the vicinity of the municipal buildings. Serbia, he said, should lower its army's alert level and make sure KFOR troops are not attacked. "Both Kosovo and Serbia should immediately recommit to engaging in the EU-facilitated Dialogue to normalize relations," said Blinken. Serbia's Defense Minister on Wednesday told the state broadcaster RTS that the "security situation is highly risky because of one-sided, illegal, illegitimate decisions by the administration in Pristina." "First of all, we should name it properly and try to define it as an occupation of the north of Kosovo by the Albanian administration in Pristina," said Vucevic. Serbian officials have repeatedly warned that Serbia would not stand idle if Serbs in Kosovo come under attack. The 1998-1999 war in Kosovo erupted when ethnic Albanian separatists launched a rebellion against Serbia, which responded with a brutal crackdown. The war ended after NATO bombing forced Serbia to pull out of the territory, and paved the way for the deployment of NATO-led peacekeepers.