"President Aleksandar Vucic, commander-in-chief of the Armed Forces, ordered to put them on a state of maximum alert," Vucevic wrote on his Twitter feed.
The digital edition of the Serbian newspaper Vecernje Novosti reported that authorities in the self-proclaimed Republic of Kosovo also alerted their forces.
Serbia Is Not Hopeful About Coming Talks With Kosovo
Currently, in Kosovo and Metohija, there is ongoing tension. Kosovo police arrested in December in the north several police officers suspected of having committed war and terrorist crimes during the 1998-1999 conflict.
Kosovar Serbs, in response, set up roadblocks in northern Kosovo to prevent police from transferring Dejan Pantic, a former Kosovo Serb policeman detained on suspicion of terrorism.
The situation at the barricades and in the municipalities of Zubin Potok, Leposavic and Zvecan is calm; Serbs stand guard there at night in tents, and there are also women during the day.
On social networks, videos are posted about the movement of military vehicles in Raska municipality and flights of Mi-35 helicopters of the country's Air Force.
The Prime Minister of self-proclaimed Kosovo, Albin Kurti, handed over Pristina's application for EU membership to the Czech Republic, which currently holds the presidency of the European Union, on December 15.
In response, the Serbian Ministry of Defense asked the KFOR high command for its consent to station a contingent of 1,000 Serbian police and military personnel on Kosovar territory based on UN Security Council Resolution 1244.
That document states that Serbia can deploy up to 1,000 military and police personnel in places inhabited by Orthodox Christians and in Serb-majority areas if the KFOR commander approves the deployment.
Kosovo, a former Serbian province populated chiefly by Albanians, proclaimed in 2008 its secession, which to date has been recognized by more than 100 countries, but not by Serbia, Russia, China, Spain, Greece, Iran, Argentina, Brazil and many others.