Lithuania's president and prime minister were forced to take shelter on Tuesday, when a drone alert caused the capital Vilnius to come to a standstill.
President Gitanas Nauseda and Prime Minister Inga Ruginiene were taken to emergency shelters following the air alert, which ordered the city's population to take cover.
Flights were suspended and road and rail travel briefly ground to a halt. The alert has since been lifted. It is not yet clear who was behind the incursion.
It came a day after Estonia said Nato shot down a drone over its territory, which it suspected was a Ukrainian projectile knocked off course by Russian electronic interference.
It was the latest in a series of recent drone incursions over Nato members Estonia, Latvia and Lithuania.
An alert from Lithuania's defence ministry on Wednesday advised citizens: Immediately take shelter in a safe place, take care of your close ones, await new recommendations.
Lithuania's national crisis management centre earlier stated it had issued an alert in response to a drone in neighbouring Belarus that was seen flying towards Lithuania.
The drone's origin had not been confirmed, the centre added. Lithuania's military later said Nato jets had been deployed to intercept the drone but could not locate it.
Additionally, an evacuation order was issued at the Seimas, Lithuania's parliament, with politicians and staff led down to a basement shelter.
On Tuesday, Estonian officials reported a Nato fighter jet had shot down a suspected Ukrainian drone. No damage was reported.
Ukraine has accused Moscow of deliberately redirecting Ukrainian drones launched at military targets within Russia and expressed apologies to Estonia and all of our Baltic friends for such unintended incidents.
The political crisis in Latvia also escalated following drone incidents, leading to Prime Minister Evika Silina resigning last week amid controversies over territorial violations.
Russia, meanwhile, continues to accuse its Baltic neighbors of allowing Ukrainian military operations from their airspace, claims that have been categorically denied by the affected states.
