Serbia will ask NATO peacekeepers to allow it to deploy the Serbian army and police in Kosovo under the terms of a UN Security Council resolution that ended the war in 1999, President Aleksandar Vucic said on Saturday, Reuters reported.

Vucic said at a press conference in Belgrade that he would make the request in a letter to NATO’s KFOR commander, although he was sure it would be rejected.

Vučić’s statement came after a series of incidents between the Kosovo authorities and the Serbs, who make up the majority in northern Kosovo.

Hundreds of Kosovo Serbs built barricades on the main road in northern Kosovo

Hundreds of Kosovo Serbs erected barricades on a road in northern Kosovo on Saturday, blocking traffic to two important border crossing points with Serbia, police said, AFP reported, Agerpres reported.

Trucks, ambulances and farm machinery were deployed to block traffic amid tensions marked by explosions, shootings and an attack on a police patrol in recent days. A Kosovo policeman was injured during the attack.

According to local media, minority Serb protesters in Kosovo are outraged by the arrest of a former ethnic Serb police officer suspected of involvement in attacks on Kosovo police officers.

Alarms went off in several predominantly Serb towns in northern Kosovo to signal the start of Saturday’s protest. The demonstrators explained to AFP that they wanted to prevent the “movement to Pristina” of the arrested former policeman.

Kosovo Interior Minister Jelal Svekla said the former policeman was one of two suspects arrested following attacks on police patrols over the past two days.

New tensions erupted after Kosovo authorities decided to hold local elections in Serb-majority municipalities on December 18, which were boycotted by the main Serbian parties.

Shortly after the barricades were lifted, Kosovo President Vjosa Osmani announced that she had decided to postpone local elections to April 23.

On November 24, Kosovo and Serbia reached an agreement to end a nearly two-year dispute over license plates in northern Kosovo. From November 24, Kosovo plans to start fining around 10,000 Serbian drivers who continue to use Serbian license plates.

This year, Kosovo tried to ask its Serbian minority to change its old license plates, which date back to 1999, when Kosovo was still part of Serbia. Serbs in the northern part of the country opposed it, sometimes violently.

About 50,000 ethnic Serbs living there refuse to recognize Pristina’s rule and still consider themselves part of Serbia.

The Kosovo-Serbia border has seen huge tensions, with Kosovo police closing two border posts in the country’s volatile north in August after local Serbs blocked several roads and shot at police in protest against the license plate order.