(Reuters) - Riot police and protesters fought running battles in Kosovo's capital Pristina on Tuesday as anti-government protests erupted into the worst unrest since the former Serbian province seceded in 2008.

A Reuters reporter saw masked police officers firing tear gas and water cannon, trying to disperse about 2,000 protesters who had taken to the streets in rallies organised by opposition political parties.

Ambulances attended to dozens of injured people as police pursued protesters into side streets around central Pristina. Demonstrators hurled rocks and bottles.

A drone flew over the city but there was no sign that any of the 5,000 NATO peacekeepers stationed in Kosovo, or hundreds of European Union police officers, would be deployed to help quell the violence.

It was the second bout of unrest since Saturday, set off by popular anger over a government climbdown over the fate of a huge mining complex claimed by Serbia.

The government of Isa Mustafa, which took office in early December, had pledged to take control of the mine, which has been held in trust by a United Nations-created privatisation body since Kosovo's 1998-99 war and threatened by myriad creditor claims.

But Mustafa backed down days later in the face of a furious response from Serbia, which claims 75 percent ownership of the Trepca mining complex, and pressure from Western embassies concerned at the possible repercussions for a fragile European Union-led dialogue between the two sides.

The protesters are also clamouring for the dismissal of an ethnic Serb minister in the mainly Kosovo Albanian government after he branded as "savages" a group of Albanians who lost relatives in the war and had protested against ethnic Serb pilgrims marking Orthodox Christmas in January.

Kosovo broke away from Serbia in 1999 with the help of NATO air strikes to halt the killing and expulsion of ethnic Albanians by Serbian forces waging a counter-insurgency war.

The territory of 1.8 million people, 90 percent of them ethnic Albanians, declared independence in 2008 and has been recognised by more than 100 countries.

But it remains impoverished and blighted by a reputation for organised crime and corruption that has deterred investment. The official unemployment rate is 45 percent.

Tuesday's violence was the worst since early 2007 when two Kosovo Albanian protesters were shot dead by Romanian United Nations police during demonstrations in Pristina calling for Kosovo to secede.