KOSOVSKA MITROVICA, Kosovo - UN police are firing tear gas at 5,000 Serb demonstrators trying to cross a key bridge in the ethnically divided city of Kosovoska Mitrovica.

Police have begun firing the canisters in an attempt to keep the protesters off the bridge separating the Serb and ethnic Albanian sides of the city.

Kosovska Mitrovica has been a flashpoint of tensions in Kosovo's restive north.

The Serbs are waving Serbian flags and chanting `Kosovo is ours!' on their fifth day of protests since Kosovo's ethnic Albanian leaders declared independence on Sunday.