PRISTINA, Kosovo (AP) — Kosovo law enforcement on Friday said one officer was injured by gunmen after increasing police presence fearing tension in northern areas dominated by the ethnic Serb minority.

A police officer was "slightly wounded” and a police car was damaged after armed men fired guns from a vehicle in the village of Serbovc, Zvecan commune, 50 kilometers (30 miles) north of the capital, Pristina, a statement said.

The injured officer was taken at the hospital and police are investigating the case.

On Thursday, police increased their presence in the four ethnic Serb-dominated communes in the north, where snap election will be held Dec. 18 following the abandonment of local posts by ethnic Serb minority representatives.

Earlier this week, some election centers were damaged and shooting was heard in those communes, raising fears of the long-simmering tensions between Serbia and its former province, Kosovo.

It's unclear whether the voting, opposed by ethnic Serbs, could be held normally in those communes.

Kosovo government’s decision to ban Serbia-issued license plates pushed Serb lawmakers, prosecutors and police officers in Kosovo’s northern communes to abandon local governing posts in early November.

Later in November, under the EU mediation and U.S. direct assistance, Kosovo and Serbia reached a deal that Serbia would stop issuing license plates with Kosovo cities’ denominations and Kosovo would cease further actions on the re-registration of vehicles.

The EU had warned Serbia and Kosovo they were on the edge of a precipice and must resolve their dispute or face the prospect of a return to their violent past.

The issue of Kosovo’s independence sparked a 1998-99 war in which about 13,000 people died. Serbia launched a brutal crackdown to curb a separatist rebellion by the territory’s ethnic Albanians. NATO bombed Serbia in 1999 to end the war.

Kosovo unilaterally broke away from Serbia in 2008. The Serbian government, with support from China and Russia, has refused to acknowledge Kosovo’s statehood. The United States and most of its European allies recognize Kosovo as an independent country.

NATO Secretary General Jens Stoltenberg has said that the NATO-led mission in Kosovo, known as KFOR, “remains vigilant.”