A police officer in Kosovo was shot in the head and wounded during attempts to bolster the government's authority in the Serb-dominated north, amid rising tensions between the authorities and local Serbs.
Special police units were attempting to seize control of two border posts which lead to Serbia when the officer was seriously wounded, the AP reports.
It is feared the incident could spark further violence. NATO officials said its commander in Kosovo, Major General Erhard Buehler, was working to help ease tensions.
The incident may have arisen due to an ongoing dispute over cross-border trade between Kosovo and Serbia, the Economist reports.
Kosovo has been prevented from exporting through or to Serbia since declaring independence from Serbia three years ago. In retaliation over the export issue, Kosovo banned Serbian imports on July 20.
The EU's civilian mission, called the European Union Rule of Law Mission in Kosovo (EULEX), issued a statement condemning the police activity and calling for disputes to be resolved in a "peaceful manner".
EULEX spokesman Nicholas Hawton said:
It is important that the current situation is resolved in a calm and peaceful manner. EULEX is coordinating closely with KFOR to do this and to maintain security. EULEX was not involved in any way in the operation carried out by special units of Kosovo Police.