Poland has said what was probably a “Russian-made missile” fell on a village in the country’s east killing two people, but that there was “no concrete evidence” on who had fired it, as its NATO allies prepared to hold an emergency meeting to discuss the strike.

The Polish foreign ministry said the weapon fell on Przewodow, about six kilometres (3-1/2 miles) from the border with Ukraine, with the country convening a meeting of its national security council.

“We do not have any conclusive evidence at the moment as to who launched this missile … it was most likely a Russian-made missile, but this is all still under investigation at the moment,” President Andrzej Duda told reporters.

Duda said it was very likely that Poland would request consultations under Article 4 at a meeting of the NATO alliance at 08:00 GMT on Wednesday. Foreign Minister Zbigniew Rau summoned the Russian ambassador and “demanded immediate detailed explanations”, the foreign ministry said.

NATO and its allies, including the United States, have said they are investigating the cause of the explosion in Poland on Tuesday.

Many global leaders are attending the Group of 20 summit on the Indonesian island of Bali, and US President Joe Biden, who is in Bali, said he had already spoken on the phone with Duda.

Biden told Duda that Washington has an “ironclad commitment to NATO” and will support Poland’s investigation, the White House said after the call.

A group including Biden, the United Kingdom’s Prime Minister Rishi Sunak and European Commission President Ursula von der Leyen held an early morning discussion on the situation and loss of life. Japanese Prime Minister Fumio Kishida was also in attendance although Japan is not a member of NATO.

The leaders were pictured around a conference table at the start of the meeting. Afterwards, Biden told reporters that early information suggested the explosion might not have been caused by a missile fired from Russia.

“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,” Biden said.

NATO chief Jens Stoltenberg said earlier he had spoken to Duda and that the alliance was monitoring the situation and consulting with its allies.

“Important that all facts are established,” Stoltenberg wrote on Twitter.

If confirmed, the strike would represent the first time a Russian missile has landed in a country other than Ukraine since Russia launched an invasion of its neighbour on February 24. The reports on Tuesday spurred widespread concern and calls to determine exactly what happened.

Al Jazeera’s Jonah Hull, reporting from Kyiv, said it was possible the missiles had “missed their targets, overshot their targets, or were pushed off course by Ukrainian air defences”.

“But I think we need to be very, very careful about speculating along those lines until the details of the attack become clearer,” Hull said.

Analysts said NATO was unlikely to escalate the situation.

Samuel Ramani, an associate fellow at RUSI in the UK, told Al Jazeera that Poland had shown a reluctance to blame Russia directly and that the attack was unlikely to meet the threshold for an Article 5 response. Article 5 is the alliance’s principle of collective defence under which an attack on one of its members is deemed an attack on all.

Russia’s defence ministry dismissed the reports on the strike as “a deliberate provocation aimed at escalating the situation”.

“No strikes on targets near the Ukrainian-Polish state border were made by Russian means of destruction,” it said in a statement.

Kremlin spokesman Dmitry Peskov also told the Reuters news agency he had no information about the explosion.

Poland’s foreign ministry said the strike took place at about 3.40pm (14:40 GMT) on Tuesday.

A resident who declined to be identified was quoted by the Reuters news agency as saying the two victims were men who were near the weighing area of a grain facility.

Prime Minister Mateusz Morawiecki said international experts as well as security specialists were on the ground in Przewodow and urged people to remain calm.

“Let’s be prudent. Let’s not let ourselves be manipulated,” he said, warning of “fake news”.

Wave of concern

Condemnation and concern swiftly rolled in from across Europe after news of the explosion broke, with many officials accusing Russia of being responsible for the incident.

Latvian Deputy Prime Minister Artis Pabriks said on Twitter that Russia “fired missiles which target not only Ukrainian civilians but also landed on NATO territory in Poland”.

Ukraine’s Foreign Minister Dmytro Kuleba called for a NATO summit, which would include Ukraine, to issue a “tough” collective response to Russia, while also urging Kyiv’s allies to provide the country with advanced weaponry and aircraft.

“Today, protecting Ukraine’s skies means protecting NATO,” Kuleba wrote on Twitter.

President Volodymyr Zelenskyy said it was a “significant escalation” of the conflict but did not provide evidence.

Meanwhile, officials from Norway, Lithuania and Estonia – all NATO members – said they were trying to find out more information.

“This is a very serious incident but much remains unclear,” Norwegian Foreign Minister Anniken Huitfeldt said, according to Norwegian news agency NTB.

The US also struck a cautious tone, with White House National Security spokesperson Adrienne Watson tweeting that the Biden administration would “determine what happened and what the appropriate next steps would be”.

US Department of State spokesperson Vedant Patel called the reports “incredibly concerning” but added the question of whether the reported strikes were intentional or accidental “would be of importance”.

Tuesday’s explosion came amid a wave of Russian strikes across Ukraine, which Kyiv called the heaviest in nearly nine months of war.

Bombings were reported in multiple cities including Lviv, which is less than 80km (50 miles) from the border with Poland.

European Union chief Charles Michel said he was “shocked by the news of a missile or other ammunition having killed people on Polish territory”.

“We stand with Poland. I am in contact with Polish authorities, members of the European Council and other allies,” he wrote, adding later that he would propose a meeting on Wednesday with EU leaders at the G20 in Bali.

PHOTO CAPTION:•Poland said security and international experts had been sent to Przewodow in eastern Poland following the blast [AP Photo] (Al Jazeera)

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