According to the General Staff of the Polish Armed Forces, a Russian missile entered the airspace of the NATO member on Friday morning.
Poland’s armed forces chief believes a Russian missile entered Poland for almost three minutes and then turned back into Ukrainian airspace.
Gen Wieslaw Kukula said the missile travelled about 40km (25 miles) into Polish airspace early on Friday.
Russia has launched a huge wave of missile strikes on Ukrainian cities, including the capital, in one of the biggest attacks on the country since the start of the war. Poland’s UN representative said Warsaw believes the incident was linked to the massive bombardment.
President Andrzej Duda convened an emergency security meeting after the object was picked up on radar.
Poland is a member of the Nato alliance, and Polish and Allied aircraft were scrambled in response to the incident at around 07:00 (06:00 GMT) on Friday. There have been no reports of an explosion.
Operational Command spokesman Lt Col Jacek Goryszewski said an unidentified object had entered Poland from Ukraine near the town of Zamosc, in the Lublin region of south-eastern Poland, not far from the border.
“Everything indicates that a Russian missile intruded in Poland’s airspace. It was monitored by us on radars and left the airspace,” said Poland’s defence chief, Gen Wiesław Kukuła.