Poland says what appeared to be a Russian missile violated its airspace on Friday, the same day Russia launched massive airstrikes against Ukraine.

Military officials said the airborne object travelled about 40 kilometers for about three minutes over eastern Poland. They said the object was then observed entering the airspace of neighboring Ukraine. They added that they tracked it by radar, but did not shoot it down.

Polish President Andrzej Duda convened an emergency security meeting with defense officials to discuss how to respond.

NATO countries are paying close attention to the incident since Poland is a member of the alliance. There has been a growing sense of tension among NATO members since a missile landed in Poland in November 2022 and killed two people.

US National Security Advisor Jake Sullivan spoke on the phone with Polish National Security Bureau chief Jacek Siewiera on Friday. The White House said Sullivan expressed solidarity with NATO ally Poland in response to the alleged airspace violation. He assured Siewiera that President Joe Biden is following the issue closely.

NATO Secretary General Jens Stoltenberg said on social media that he had spoken with Duda about the incident. He said NATO stands in solidarity with what he described as a valued ally and is monitoring the situation. "We will remain in contact as the facts are established," Stoltenberg said. "NATO remains vigilant."