PRISTINA -- European diplomats are warning that a dispute pitting Serbia and Russia against Kosovo over a series of raids by Kosovar police in the country's Serb-dominated north threatens to ignite the Balkan tinderbox.
Serbia put its army on high alert and moved some troops near the border with Kosovo as the two sides traded allegations on May 29, after the Kosovar police operation the previous day saw 19 local police officers arrested for allegedly being involved in "criminal activities."
The raids that took place in several municipalities, including Zubin Potok, Mitrovica North and South, and Skenderaj, also resulted in the detention of six ethnic Serbs and of two members of the UN mission in Kosovo, including a Russian citizen. They are accused of hampering the police operation.
The two UN staff members have been released, but the Russian's detention pulled Moscow, Belgrade's traditional ally, into the fracas.
The district prosecutor in Mitrovica, through the Ministry of Foreign Affairs of Kosovo, has demanded waiving diplomatic immunity for the Russian, saying he participated in trying to block the police with barricades.
Aleksandr Chepurin, Russia's ambassador to Serbia, blasted the suggestion to strip the Russian, Mikhail Krasnoshchekov, of immunity, saying, "It is a brazen attack on a staffer of the UN mission" to Kosovo.
The raids have brought simmering tensions to a boil in a region that is known for its instability, prompting European Union foreign-policy chief Federica Mogherini to warn the incident "shows us that the status quo is not sustainable and that both Pristina and Belgrade need to come back to the dialogue table."
"I see the risk of the dark forces of the past coming back, in terms of confrontation, even of conflict" if the two sides continue facing off, Mogherini added.
Serbia claimed it was caught off-guard by the raid, which Kosovar officials said resulted in five police officers and six civilians being injured, but a spokesman for the NATO-led Kosovo Force (KFOR) told RFE/RL that there was "continuous" communication between Pristina, the peacekeepers, the international community, and the Serbian military.
"It's true they knew," spokesman Vincenzo Grasso said, adding: "I'm surprised everyone is surprised. We have continuous communication and during the operation there was a constant information exchange and everybody was informed. We have been informed the day before."
The European Union, the United Nations Interim Administration Mission in Kosovo (UNMIK), and KFOR all quickly called for calm, but emotions continued to run high.
Hundreds of people joined a demonstration in Mitrovica in protest at the Kosovar police operation. The head of Kosovo's main ethnic Serb party, Goran Rakic, said that civilians had been beaten just because they were Serbs.
During a visit to Slovenia, Russian Foreign Minister Sergei Lavrov said the incident was instigated by "those who want to create a buffer zone from Russia on the Balkans" and who "want to push everyone to NATO."
The Russian arrested in the police raid, Krasnoshchekov, was held for several hours and accused of "interfering with an official during the exercising of their duties" and "participating in a mass criminal act of hooliganism."
In a statement, UNMIK said that the Russian national was a civil-affairs officer and "the most senior officer" based in Zubin Potok. He was taken to the hospital, where he is being treated for injuries it added.
Milan Ivanovic, director of the Serbian Health Center in North Mitrovica, said that Krasnoshchekov had been "seriously injured" during the arrest and that he would be transferred to the Military Medical Academy in Belgrade for further treatment.
The other UNMIK staff member is a "Kosovo Serb" working as a program management assistant in the municipality, UNMIK said, adding that the man suffered injuries and was taken to the hospital for examination during his detention.
"Whilst details are being clarified, the staff involved were acting in an official capacity when they were arrested and detained. In addition, there are serious allegations raised that police applied force against clearly identified UN staff, which exceeds reasonable standards," UNMIK said.
Under international and Kosovar law, the statement added, all UNMIK personnel are "immune from legal process in respect of words spoken and all acts performed by them in their official capacity. Requests for waiver of immunity received by UNMIK are forwarded to United Nations headquarters for a decision by the secretary-general of the United Nations."
Kosovo's ethnic Albanian majority declared independence from Serbia in February 2008. Although more than 110 countries recognize Kosovo, Belgrade and Russia do not.