Poland said it scrambled fighter jets and shot down Russian drones that crossed into its airspace, calling it "an act of aggression" and a "large-scale provocation" against the NATO and European Union member.
It was the first time a NATO nation has fired shots since Russia launched its full-scale invasion of neighboring Ukraine in February 2022, and Poland requested NATO consultations under a treaty article addressing external threats.
"Last night the Polish airspace was violated by a large number of Russian drones. Those drones that posed a direct threat were shot down," Prime Minister Donald Tusk told an emergency government meeting on September 10.
"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," Tusk later told parliament, saying this is "the closest we have been to open conflict since World War II."
As condemnations of Russia from European leaders poured in, Tusk said there were 19 intrusions into Polish airspace overnight, with several drones flying in from Belarus, and that four were likely shot down.
However, Interior Ministry spokeswoman Karolina Galecka said "seven drones and debris of one missile of unidentified origin" had been found.
Poland Invokes NATO Article 4
"The fact that these drones, which posed a security threat, were shot down changes the political situation. Therefore, allied consultations took the form of a formal request to activate Article 4 of the NATO Treaty," Tusk said.
Article 4 states members "will consult together whenever, in the opinion of any of them, the territorial integrity, political independence or security of any of the Parties is threatened." A NATO spokesperson said it was the first time its planes had engaged potential threats in allied airspace.
NATO Secretary-General Mark Rutte said that whether the airspace violation was intentional or not, "it was absolutely reckless," and that NATO's reaction was "very successful."
"My message to [Russian President Vladimir] Putin: Stop the escalating war in Ukraine, stop violating allied airspace, and know that we are vigilant and will defend every inch of NATO territory," Rutte said after a meeting of the North Atlantic Council, the alliance's main political decision-making body.
Tusk said there were no casualties in the incursion into Polish airspace, which came amid a massive attack on Ukraine.
Ukrainian President Volodymyr Zelenskyy said Russia targeted 15 regions, firing at least 415 drones and more than 40 missiles. At least one person was killed and three others wounded, he said, repeating his call for a stronger Western response.
"Moscow always pushes the boundaries of what is possible, and if it does not encounter a strong reaction, it remains at the new level of escalation," he said.
Russia Says 'No Evidence'
Russia's charge d'affaires in Poland, Andrei Ordash, told Russian state news agency RIA Novosti that Moscow considers "the accusations to be unfounded. No evidence has been provided to show that these drones are of Russian origin."
Kremlin spokesman Dmitry Peskov declined to comment, saying it was a matter for the Defense Ministry.
While discussing further sanctions pressure on Russia, Kyiv's Western backers are also trying to hammer out plans for a postwar "reassurance force."
But the unprecedented incident comes as peace talks founder, with Russian President Vladimir Putin refusing to meet with Zelenskyy and vowing to achieve his goals by force if necessary as Moscow's troops press to take more territory, particularly in the Donetsk region in the east.
EU Leaders Condemn Russian Drone Incursion
"Last night in Poland, we saw the most serious European airspace violation by Russia since the war began, and indications suggest it was intentional, not accidental," EU foreign policy chief Kaja Kallas wrote on X. "The EU stands in full solidarity with Poland. Russia's war is escalating, not ending."
"The incursion of Russian drones into Polish airspace during an attack conducted by Russia against Ukraine is simply unacceptable.... I call on Russia to put an end to this reckless escalation," said French President Emmanuel Macron.
Hungarian Prime Minister Viktor Orban also called the "violation of Poland's territorial integrity...unacceptable," saying it underscored the need for peace. British Prime Minister Keir Starmer said it was "extremely reckless" and demonstrated "Putin's blatant disregard for peace."
"Russia's plan to destroy Ukraine is just the beginning of its ambition in Europe," said Czech Prime Minister Jan Lipavsky. 'No matter where peace is reached in Ukraine, Putinism will remain the main threat to European security."
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