Poland has accused Russia of sending several drones into its territory, with prime minister Donald Tusk saying the country is the closest it has been to armed conflict since the Second World War.
Polish air defences shot down at least three drones, marking the first time a Nato member has directly engaged Russia since the beginning of its war in Ukraine.
Mr Tusk has called for an emergency meeting of the Nato council as he announced that there had been 19 incursions by drones and drone-like objects into Polish airspace overnight.
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“I have no reason to claim we’re on the brink of war, but a line has been crossed, and it’s incomparably more dangerous than before,” he said.
“This situation brings us the closest we have been to open conflict since World War Two”.
At least three drones which Poland believed posed a threat to its territory were shot down, Mr Tusk said. It was likely that a fourth had been downed, but Warsaw was awaiting confirmation.
Local authorities in Wyryki, eastern Poland, said a drone or similar object had struck a residential building, but nobody was injured. Debris was also found in the nearby town of Wyhalew.
Police in the village of Czosnowka, in Poland’s eastern Lublin region, said they had found a damaged drone, while the District Prosecutor’s Office in Zamosc, also in Lublin, said drone components had been discovered near a cemetery in the town of Czesniki.
In the central Lodz region, a drone was found in a field near the village of Mniszkow, Reuters reported. Debris was also found in Olesno, 400 kilometres inside Poland.
Meanwhile, Interior Ministry spokesperson Karolina Galecka said Poland had found seven drones and debris from a missile.
Ukrainian president Volodymyr Zelensky has claimed that Poland was deliberately targeted during a Russian drone attack overnight.
“Increasing evidence indicates that this movement, this direction of strike, was no accident,” he wrote on X. “Ukraine is also ready to help Poland build an effective system of warning and protection against such Russian threats.”
But Nato is not currently treating it as an attack on one of its member states, a source in the alliance told Reuters.
The drone incursion has drawn widespread condemnation from across Europe, including EU Council president Antonio Costa who said the bloc stands in full solidarity with Poland, adding that the “security of one is the security of all”.
The incursion is “simply unacceptable”, French president Emmanuel Macron said on X, as he condemned it in the “strongest possible terms”.
The EU’s top diplomat Kaja Kallas condemned the “most serious European airspace violation by Russia since the war began” and said that “indications suggest it was intentional, not accidental”.