UN police stormed a courthouse in northern Kosovo on Monday and removed Serb protesters, setting off clashes that injured dozens of international peacekeepers and demonstrators.
Hundreds of Serb protesters outside the UN courthouse hurled rocks and hand grenades at UN police and NATO troops, who responded with tear gas and stun grenades.
It was the worst violence in Kosovo since its majority ethnic Albanians declared independence from Serbia a month ago.
NATO troops came under fire during Serb riots in the northern Kosovo flashpoint of Mitrovica on Monday, in the worst violence in the territory since the Albanian majority declared independence last month.
The rioting was a challenge to the authority of NATO, the United Nations and a fledgling European Union justice mission, underscoring fears that Kosovo could be heading for ethnic partition exactly one month after breaking away from Serbia.
Reuters witnesses in the town reported hearing gunfire as hundreds of Serbs clashed with the NATO peacekeeping force KFOR, and with UN police. A French NATO spokesman said automatic weapons fire had been aimed at peacekeepers, but gave no further details.
The violence began at dawn when several hundred UN special police backed by NATO peacekeepers stormed a UN court that had been seized by Serbs on Friday, and arrested dozens.
Hundreds of Serbs fought back with stones, grenades and firecrackers, forcing the UN police to pull back and leave KFOR to face the rioters.