Kosovo and Serbian institutions on Wednesday said Serbian police had arrested three Kosovo police officials in an action that Kosovo authorities called “kidnapping”.

Both countries gave contradictory claims regarding the location of the arrest.

The Director of Serbia’s Office for Kosovo, Petar Petkovic, said the officers were arrested in Serbian territory near the border with Kosovo, but Kosovo’s government claims they were arrested inside Kosovo, close to the border with Serbia.

A clear border line between Kosovo and Serbia was never determined by a demarcation agreement because Serbia does not recognise Kosovo’s independence and considers the border an “administrative line” and not an international border.

Petkovic said that three of Kosovo PM Albin “Kurti’s Special police members” were arrested in the village of Gnjilica, in Raska municipality, “deep in the territory of central Serbia”.

“Members of our police did not set foot on the territory of Kosovo and Metohija”, Petkovic told the media, claiming that Serbia is ready to “offer all evidence” for this.

Serbian authorities claim the three policeman were heavily armed.

But Kurti said that “three Kosovo police officials have been kidnapped today in Leposavic in the place where there used to be an illegal smuggling route, which is located 300 meters within the territory of our state”.

“We suspect that they were kidnapped by the Serbian army, clearly as revenge by Serbia for yesterday’s arrest of the notorious criminal Milun ‘Lune’ Milenkovic, who represents one of the leaders of organized crime and smuggling,” Kurti wrote on Facebook.

“We request the immediate release of three kidnapped police officers and call on international factors to condemn this aggression by Serbia,” Kurti said.

Milenkovic was arrested on Tuesday by the Kosovo police in the Serb-majority northern municipality of North Mitrovica on suspicion of orchestrating attacks against NATO peacekeepers at the end of May.

A Kosovo Police press release said that three patrolling border police officers “were kidnapped deep in Kosovo territory”.

“The border patrolling unit has been on duty in a static checkpoint at the location called Tresave/Bare… to prevent the use of illegal roads, which have been used by illegal groups for illegal crossing and smuggling,” police said.

“Today at noon, the police unit which was composed of three officers, informed that in the vicinity of static checkpoint they spotted masked and armed persons. On this occasion, additional assistance units departed [to the scene]. On arrival, the assisting units saw only the official vehicle, but not police officers,” it added.

Kosovo Police said they had informed KFOR and other security institutions “because there are suspicions that police officers have been kidnapped”.

Petkovic said the Serbian police had “obviously prevented” the arrested people “in their intention to commit a dangerous criminal act”.

“The investigation will determine which criminal offence it is about and what was actually the intention.”

The incident happened amid calls by the international community for Kosovo to de-escalate the situation in the Serb-majority north, where since May 26 local Serbs have been protesting against newly elected mayors.