Petras Malukas | Afp | Getty Images
The object was likely a drone which entered from Poland, defense minister Robertas Kaunas told reporters, adding that he had proposed a joint investigation with his Polish counterpart.
Poland’s military said it was also verifying a possible violation of its airspace by an unidentified object.
During the “red” alert, NATO air police fighters were scrambled to the area and Kaunas airport, near Lithuania’s second-largest city, was temporarily closed, the crisis management center said.
The NATO aircraft were unable to visually identify the object due to cloudy weather and did not attempt to shoot it down, the center said.
Lithuanian army personnel were investigating possible drone debris near Juodzionys village in northern Lithuania, after the object disappeared from radar, the center said.
Some of the debris struck a civilian vehicle, Kaunas said.
NATO did not immediately respond to a request for comment.
Northern neighbor Latvia briefly issued a “yellow” air warning in some regions bordering Lithuania, citing a “possible threat”, Latvia’s army said.
Ukrainian drones have repeatedly entered NATO airspace in the Baltic region in recent months. Kyiv has said they were steered off course by Russian signal jamming.
This has stoked concerns that Russia’s war in Ukraine is spilling over NATO’s borders.