The explosion on Tuesday at a grain facility in the Polish village of Przewodów near the Ukrainian border came as Russia fired dozens of missiles against cities across Ukraine in a new wave of attacks targeting critical energy infrastructure, according to officials.
"Although we do not know the exact causes of the tragedy in Przewodów, we do know the primary cause - Russia's aggression against Ukraine," Polish Prime Minister Mateusz Morawiecki told parliament in Warsaw on Wednesday.
"This tragedy would not not have happened if Russia had not launched a massive missile attack on Ukraine yesterday," he added.
"We cannot rule out that the shelling of Ukrainian infrastructure near the border was an intentional provocation done in the hope that such a situation could arise," Morawiecki told lawmakers.
He said, as quoted by his office: "Yesterday in Przewodów, an explosion took place, which killed two citizens of Poland. Now is the time for an in-depth investigation by all services, a joint condemnation of Russia by the international community and a tough response from NATO and the European Union."
'We have very strong external support'
Morawiecki told MPs that Poland was safe amid Russia's war in neighbouring Ukraine, Polish state news agency PAP reported.
He said: "We have very strong external support. The most powerful military alliance in history stands behind us: NATO."
He added that leaders from many countries were "declaring their full support" for Poland "and full support in defending Ukraine's sovereignty."
'Incident was likely caused by Ukrainian air defence missile': NATO chief
NATO Secretary-General Jens Stoltenberg said on Wednesday that the missile that killed two people in southeastern Poland was probably a stray fired by Ukraine's air defences and not a Russian strike.
He added, however, that Russia "bears ultimate responsibility" for the incident as it "continues its illegal war" against Ukraine.
"We have no indication that this was the result of a deliberate attack and we have no indication that Russia is preparing offensive military actions against NATO," Stoltenberg told reporters in Brussels on Wednesday.
He said, as quoted on the nato.int website: "Our preliminary analysis suggests that the incident was likely caused by a Ukrainian air defence missile fired to defend Ukrainian territory against Russian cruise missile attacks."
"But let me clear: this is not Ukraine's fault," Stoltenberg added after an emergency meeting of NATO ambassadors. "Russia bears ultimate responsibility as it continues its illegal war against Ukraine."
'Russia bears ultimate responsibility': Stoltenberg
NATO ambassadors on Wednesday held emergency talks in Brussels to respond to Tuesday's incident in southeastern Poland, which marked the Ukraine war's first deadly spillover onto NATO territory, the Reuters news agency reported.
'I thanked allies for their support and solidarity': Polish NATO ambassador
Poland's ambassador to the Western military alliance, Tomasz Szatkowski, said he briefed the meeting "on the situation in the aftermath of yesterday’s tragic events in southeastern Poland" and the ongoing investigation.
"We are in close contact with Secretary-General Jens Stoltenberg and NATO Allies as we stay vigilant and continue the investigation," Szatkowski said in a tweet.
"I thanked Allies for their support and solidarity," he added.
Ukraine requests access to explosion site in Poland
Meanwhile, a senior Ukrainian defence official, Oleksiy Danilov, said that Ukraine requested "immediate access to the site of the explosion."
Danilov tweeted: "We advocate for a joint examination of the incident with the missile’s landing in Poland. We are ready to hand over evidence of the Russian trace that we have. We are expecting information from our partners, based on which a conclusion was made that it’s a Ukrainian air defense missile."
'I have no doubt that it was not our missile': Ukraine's Zelensky
Ukrainian President Volodymyr Zelensky was quoted as saying on Wednesday that he had no doubt the explosion in Poland was not caused by a Ukrainian missile.
"I have no doubt that it was not our missile," Zelensky said, as quoted by the Interfax Ukraine news agency.
Zelensky earlier blamed the incident on "Russian missile terror."
'No indication' missile strike was intentional: Polish president
Earlier in the day, Polish President Andrzej Duda said that there was no indication that the missile was intended to hit Poland amid Russia's war in neighbouring Ukraine.
"There is no indication that this was an intentional attack on Poland," Duda said before an emergency meeting of Poland's National Security Council on Wednesday.
"It was not a rocket aimed at Poland," he added.
'S-300 rocket' probably 'fired by Ukrainian anti-aircraft defense'
"From the information that we and our allies have, it was an S-300 rocket made in the Soviet Union, an old rocket and there is no evidence that it was launched by the Russian side," Duda told reporters in between meetings with senior government, security and military figures.
"It is highly probable that it was fired by Ukrainian anti-aircraft defense," he also said during a joint news conference with the Polish prime minister.
'We are dealing most probably with an unfortunate event': Polish PM
Poland's Morawiecki told reporters: "There is no indication that yesterday's event was an attack on Polish territory. We are dealing most probably with an unfortunate event, as a result of which Polish citizens died."
He offered his condolences to the families of the victims.
He said: "We will take care of these families and strengthen our presence and the presence of our allies' air forces on Poland's eastern border. It is proof of NATO's strength and increased security."
Morawiecki stated, as quoted by his office: "Ukrainian forces, countering a massive Russian attack, launched their missiles yesterday to shoot down Russian missiles. There are many indications that one of these missiles fell on Polish territory without any intention on either side."
He also said that Poland was still examining the possibility of invoking Article 4 of NATO's founding treaty, which calls for consultations when a member country considers its security under threat, the Reuters news agency reported.
Article 4 of the North Atlantic Treaty states that “The Parties will consult together whenever, in the opinion of any of them, the territorial integrity, political independence or security of any of the Parties is threatened,” Polish state news agency PAP reported.
Morawiecki told the media that NATO ambassadors were holding an emergency meeting on Wednesday to discuss the incident in southeastern Poland.
'It is unlikely in the lines of the trajectory that it was fired from Russia': Biden
US President Joe Biden said earlier in the day that the missile that killed two people in NATO member Poland was probably not fired from Russia.
Biden was speaking after talks with leaders of Western allies gathered for a G20 summit in Bali, Indonesia, Reuters reported.
Biden tweeted: "I’m discussing a meeting with world leaders on the loss of life in eastern Poland and the United States’ commitment to support Poland’s investigation."
Leaders from NATO members Germany, Canada, Netherlands, Spain, Italy, France and Britain took part in the meeting, as well as non-NATO member Japan and representatives from the European Union of which Poland is part, according to the Reuters news agency.
Asked whether it was possible to say if the missile was fired from Russia, Biden said: "There is preliminary information that contests that. I don't want to say that until we completely investigate it, but it is unlikely in the lines of the trajectory that it was fired from Russia but we’ll see.”
'Our full support for Poland's investigation of the explosion'
Biden said in a tweet that he spoke with the Polish president "to express my deep condolences for the loss of life in eastern Poland and offer our full support for Poland's investigation of the explosion."
'Russia-made missile dropped on village of Przewodów': Polish foreign ministry
The Polish foreign ministry said in a statement on Tuesday that the rocket fell on Przewodów, a village about 6 km from the border with Ukraine.
"On 15 November 2022, another hours-long, massive shelling took place of the entire territory of Ukraine and its critical infrastructure by the armed forces of the Russian Federation," the statement said.
"At 3:40 pm, a Russia-made missile dropped on the village of Przewodów, district Hrubieszów, Lubelskie province, and resulted in the death of two citizens of the Republic of Poland," it added.
Poland summons Russian ambassador
The Polish foreign ministry also said that Poland's top diplomat Zbigniew Rau summoned the Russian ambassador "and demanded immediate and detailed explanation."
Russia denied it was responsible for the explosion, Reuters reported.
Wednesday was day 266 of the Russian invasion of Ukraine.
Source: IAR, PAP, Reuters, nato.int