Serbia refuses to recognize Kosovo’s 2008 declaration of independence and has repeatedly threatened it will defend local Serbs by “all means” if they are assaulted.

The Serbian security forces on the Kosovo border have been placed in “maximum combat preparedness.”

The order was issued by the interior minister of Serbia, Bratislav Gasic, who stated that he was acting on instructions from President Aleksandar Vucic to “take all steps to defend the Serbian population in Kosovo.”

Kosovo has made no response to the action.

It follows weeks of rising tension between the two sides, during which ethnic Serbs in Kosovo said they were mistreated by the ethnic Albanian majority.

In 1999, the war in Kosovo was terminated by NATO intervention.

Serbia refuses to recognize Kosovo’s 2008 declaration of independence and has repeatedly threatened it will defend local Serbs by “all means” if they are assaulted.

Last month, ethnic Serb mayors, judges, and police officials in northern Kosovo resigned in protest at the government’s intention to replace Serbian-issued car license plates with Pristina-issued plates.

This month, thousands of Kosovo Serbs protested, demanding that the Albanian majority government withdraw police from the north.

Since 10 December, around 50,000 Serbs have created nine roadblocks in the northern area of Kosovo, where they reside.

Even though no one was injured in a Sunday shooting near a NATO peacekeeping patrol in one of the northern towns, NATO has stated that it is conducting an investigation and has asked for calm.

The European Union has been attempting to arbitrate between the two sides, and Serbia, which has been armed with Russian support, has agreed to engage in dialogue.