Poland invoked Article 4 of the North Atlantic Treaty on Wednesday after fighter jets shot down multiple Russian drones that illegally entered Polish airspace.

Russia, which has been at war with Ukraine along Poland's southeastern border, has said it didn't mean to send drones into the airspace, but the move has prompted outcry from NATO allies.

"What is clear is that the violation last night is not an isolated incident," NATO Secretary General Mark Rutte told reporters Wednesday. "Whether it was intentionally or not, it is absolutely reckless. It is absolutely dangerous."

The North Atlantic Treaty Organization, commonly known as NATO, is a defense alliance that the U.S., Canada and several European countries created after World War II. Poland joined the alliance in 1999.

Article 5 is

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