Separately, Romanian fighter jets were launched as Russia attacked Ukrainian territory near the nations’ shared border near the Danube River. A UAV was detected inside Romania’s airspace, the defense ministry said. 

Poland’s air defense systems were placed on the highest alert “amid the threat of Russian drones” over Ukraine, Prime Minister Donald Tusk said in a separate post, adding that the action was “preventive.”

Residents of six Polish districts near to the Ukrainian border received emergency SMS alerts warning of a threat from the air.

Ukraine’s air defense said earlier on Saturday that two Russian UAVs had been flying in the west of the country. 

Ukrainian President Volodymyr Zelenskiy said in a post on X Saturday that he didn’t think the drone flights were accidental as he renewed his call for the country’s allies to impose additional sanctions on Russia. 

Read more: Poland To Trump: Russian Drone Incursion Wasn’t a Mistake

Poland has became highly attuned to its air security after an unprecedented incursion of about 20 Russian drones earlier this week. Polish and allied forces shot down at least three UAVs for the first time since Russia’s full-scale invasion of Ukraine in 2022. 

The country is set to receive additional air defense support from its North Atlantic Treaty Organization’s allies as a result of the events. 

Read more: Poland Seeks NATO Consultations After Downing Russian Drones

US Secretary of State Marco Rubio said Saturday that it will take a few days to determine whether the drones were intentionally sent into Poland.

“The question is whether the drones were targeted to go into Poland specifically,” he told reporters as he departed for a trip to Israel. “If that’s the case, that the evidence leads us there, then obviously that’ll be a highly escalatory move.”