A shootout between police and heavily armed persons in northern Kosovo was underway on Sunday, just hours after an ambush incident left one police officer dead and another injured.
"We see armed, uniformed people, heavy weapons, they are shooting at us, we are shooting," said Veton Eljsani, deputy commander of the Kosovo Police for the North region, according to CNN affiliate N1.
Eljsani would not confirm who the armed individuals are, according to N1.
The incident is a serious escalation in a region already prone to unrest. Kosovo is majority Albanian, but like other villages in the north, Banjska -- where there the shootout is taking place -- is predominantly Serbian.
Kosovo declared independence from Serbia in 2008 but Serbia sees Kosovo as a breakaway state. Kosovo's Serbs view themselves as part of Serbia, and see Belgrade as their capital, rather than Pristina.
Overnight Saturday into Sunday, a border police unit noticed two heavy trucks without license plates blocking the entrance to a bridge in Banjska, according to N1. Police units were deployed to the area.
When police officers arrived at the scene, they encountered resistance, shots were fired, and during the exchange of fire one police officer was killed and another was injured, according to N1. Kosovo police said they were shot at with "an arsenal of firearms," including hand grenades and stun guns.
In a post on Facebook Sunday morning, Kosovo Prime Minister Albin Kurti described the shooting in the village of Banjska as a "terror attack" conducted by what he said were "Serbian criminal gangs."
CNN has reached out to Serbia's Foreign Ministry for comment about the incident.
In a statement Sunday, EU's foreign policy chief Joseph Borrell condemned the attack and called for a de-escalation of the situation.
"I condemn in the strongest possible terms the hideous attack by an armed gang against Kosovo Police officers in Banjska/Banjskë in the north of Kosovo, which left one police officer dead," he said in a statement. "The responsible perpetrators must face justice."
"More innocent lives are at risk in ongoing hostilities in the surroundings of Banjska Monastery. These attacks must stop immediately," he added.
The EU mission in Kosovo EULEX, "as second security responder, is on the ground and in close contact with the authorities and KFOR," the NATO-led international peacekeeping force in Kosovo, Borrell said.
"The EU and its Member States repeatedly urge all actors to work to de-escalate the situation in north of Kosovo," he said.
Tensions between Kosovo and Serbia have escalated in recent months with violent protests erupting in May over controversial local elections. Dozens of NATO peacekeepers were injured in the clashes at the time.
Kosovo's Serbs have increasingly demanded greater autonomy from the ethnic Albanian majority.