Editor’s note: The story was updated with additional details.

A railway track between Warsaw and Lublin was blown up in an “unprecedented act of sabotage,” Polish Prime Minister Donald Tusk announced on Nov. 17.

The Polish prime minister noted that the route is “crucially important for delivering aid to Ukraine.”

“We will catch the perpetrators, whoever they are,” Tusk said on X.

Warsaw has been raising alarm over the mounting cases of sabotage and espionage activities targeting Poland in recent years, with numerous incidents linked to Russian or Belarusian intelligence services.

Local police said a train driver reported damage on the railway line on Nov. 16. The explosion occurred near the village of Mika in the Masovian province, some 130 kilometers (80 miles) from the Polish-Ukrainian border.

According to Tusk, the explosion was likely intended to blow up a train. Polish authorities have launched an investigation into the incident and are inspecting another segment of the railway that was also damaged.

Article imageA map showing the approximate location of the explosion. (Nizar al-Rifai/The Kyiv Independent)

The Polish military will examine approximately 120 kilometers (75 miles) of the railway track leading to the Ukrainian border, Polish Defense Minister Wladyslaw Kosiniak-Kamysz said.

Ukraine’s Foreign Minister Andrii Sybiha affirmed Kyiv’s “solidarity with friendly Poland following an act of sabotage” and said Ukraine is ready to assist.

The Ukrainian top diplomat voiced hope that the investigation would soon provide answers, while suggesting it could have been another Russian hybrid attack designed to “test responses.”

Poland has said Russia has intensified hybrid operations against the country due to the Polish support for Ukraine amid the all-out war.

Sharing a 535-kilometer (332-mile) border with Ukraine, Poland has served as a key hub for delivering allied military assistance to Kyiv.

In early September, Polish and allied forces shot down several Russian drones that violated Poland’s airspace amid an air strike on Ukraine, marking the first such engagement by NATO during the full-scale war.

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