Russia and Ukraine traded strikes overnight as Russians prepared to vote in parliamentary elections. The Kremlin's main party, United Russia, is poised to retain its grip on power. The only party that had criticised the war was removed from the ballot.
Poland said it scrambled military planes in response to a Russian attack in western Ukraine, close to its border. Airports in Rzeszow and Lublin were temporarily closed, and residents of two eastern Polish regions received air raid warnings. Local media reported that sirens had sounded and that pupils in some schools had sought shelter.
Polish Prime Minister Donald Tusk said a petrol station near the town of Dorohusk, close to the Polish border, was most likely struck again. On Sunday, a Russian drone had hit a passenger train in Ukraine just two kilometres from the Polish border.
Tusk addressed parliament on Thursday, warning that intelligence assessments indicate Russia is planning drone and missile strikes against countries supporting Ukraine, including Poland.
"According to intelligence assessments, Russia's plan ... includes hybrid drone and missile strikes against countries supporting Ukraine, including Poland," Tusk said.
He said the strikes would be designed to weaken NATO's collective resolve and ability to respond to aggression against a member state.
"These potential strikes would be quote-unquote 'accidental' in nature, intended to paralyse or at least weaken the resolve of NATO states to invoke the relevant NATO provisions in the event of aggression against a member country," Tusk added.
He did not elaborate on which intelligence agencies had provided the warning.
Tusk also said such attacks could coincide with political shifts in certain European countries, where parties he described as increasingly invoking slogans of peace and pacifism could come to power.
"Political changes in certain European countries granting power - or at least a powerful voice - to those who, increasingly invoking noble slogans of peace, pacifism and needless casualties, will call for peace - or rather, the total capitulation of Ukraine," he said.
He appeared to be referring to the rise of parties such as Alternative for Germany and National Rally in France.
European countries have also suspected Moscow of being behind a series of acts of sabotage in recent months, aimed at pressuring allies supporting Ukraine. The Kremlin has vigorously denied involvement.
Polish Defence Minister Wladyslaw Kosiniak-Kamysz said Poland was strengthening its airspace protection. "We have increased F-16 and helicopter activity, and are reinforcing our air defence and rapid response systems," he wrote on social media.
Tusk said he would visit Ukrainian President Volodymyr Zelenskyy on Friday to discuss cooperation within the Integrated Anti-Ballistic Missile Coalition, a group of European countries developing an air defence system with Ukraine as a cheaper alternative to the US-built Patriot.
