Russia and Serbia have blamed pro-NATO and Western influences for an armed raid by Kosovo police in the Serb-dominated north of Kosovo that raised tensions in the region.

Russian Foreign Minister Sergey Lavrov said Wednesday that Tuesday’s 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 armed operation angered Serbia, which immediately put the Serbian army on full alert in response. A Russian U.N. employee was among more than two dozen people arrested.

A woman standing at a balcony looks at a protest against Kosovo police action in the northern Serb-dominated part of ethnically divided town of Mitrovica, Kosovo, Wednesday, May 29, 2019. Russia and Serbia have blamed NATO and the West for an armed raid by Kosovo police in the Serb dominated north of Kosovo when a Russian U.N. employee was among more than two dozen people arrested in what Kosovo says was an anti-organized crime operation. (AP Photo/Visar Kryeziu)
A woman standing at a balcony looks at a protest against Kosovo police action in the northern Serb-dominated part of ethnically divided town of Mitrovica, Kosovo, Wednesday, May 29, 2019. Russia and Serbia have blamed NATO and the West for an armed raid by Kosovo police in the Serb dominated north of Kosovo when a Russian U.N. employee was among more than two dozen people arrested in what Kosovo says was an anti-organized crime operation. (AP Photo/Visar Kryeziu)

Serbian President Aleksadar Vucic says NATO-led peacekeepers in Kosovo “lied” when they said they had informed Belgrade in advance of the police action.

The raid was the latest flare-up in long-simmering tensions between Serbia and its former province.

Kosovo Serbs protest against Kosovo police action in the northern Serb-dominated part of the ethnically divided town of Mitrovica, Kosovo, Wednesday, May 29, 2019. Russia and Serbia have blamed NATO and the West for an armed raid by Kosovo police in the Serb dominated north of Kosovo when a Russian U.N. employee was among more than two dozen people arrested in what Kosovo says was an anti-organized crime operation. (AP Photo/Bojan Slavkovic)
Kosovo Serbs protest against Kosovo police action in the northern Serb-dominated part of the ethnically divided town of Mitrovica, Kosovo, Wednesday, May 29, 2019. Russia and Serbia have blamed NATO and the West for an armed raid by Kosovo police in the Serb dominated north of Kosovo when a Russian U.N. employee was among more than two dozen people arrested in what Kosovo says was an anti-organized crime operation. (AP Photo/Bojan Slavkovic)