The Russian invasion of Ukraine took another turn in the morning of Nov. 16, as reports emerged that a missile struck a village in Poland's territory, resulting in two casualties.
However, the origins of the missile are unclear at time of publication.
Missile could be Russian-made, but Polish president being cautious
According to AP, Polish media reported that a missile hit the village of Przewodów, which lies near the Ukrainian border.
AP cited the Polish Foreign Ministry, who said that the missile was "Russian-made".
However, Poland's President Andrzej Duda was more cautious, saying that it was "most probably" Russian-made, but officials did not know that for sure at the moment, nor where it was fired from.
The Washington Post reported that the Russian Defence Ministry denied striking targets in or near Poland.
Poland is a member of the North Atlantic Treaty Organization (NATO), a military alliance between several European countries and the United States.
Article 5 of the treaty holds that an armed attack on any member of the organisation is considered an attack on every member.
"An armed attack against one or more of [the members] in Europe or North America shall be considered an attack against them all."
This raises the possibility of the use of force against the aggressor.
If that aggressor is Russia, which is a nuclear-armed state, and Article 5 is invoked, that would put it in direct conflict with NATO, which includes three nuclear-armed states -- France, the UK and the U.S.
Article 5 unlikely to be invoked
However, it is unlikely that Poland will invoke Article 5, at this moment.
CNN reported that Poland is considering invoking Article 4 of NATO instead.
Article 4 reads: "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."
This is a less escalatory step that will involve discussions. AP reported that Jens Stoltenberg, NATO's secretary general, has called an emergency meeting of the Alliance's envoys. AP added:
"In their statements, Poland and NATO used language that suggested they were not treating the missile blast as a Russian attack, at least for now.
Poland’s statement did not address the circumstances of the strike, including whether it could have been a targeting error or if the missile could have been knocked off course by Ukrainian defences. A NATO statement called it a “tragic incident."
2015 Russian air force plane incident
This would also not be the first time that Russia has come into conflict with a NATO member, if it turns out that the missile has Russian origins.
Back in 2015, Turkish air forces shot down a Russian air force plane that supposedly strayed within its borders, although Russian President Vladimir Putin maintained that the plane was in Syrian territory.
Turkey is a member of NATO.
Russia later said that Turkey's President Tayyip Erdogan had apologised for the incident.
Unlikely that missile was fired from Russia: Joe Biden
U.S. President Joe Biden, currently in Southeast Asia for the Asean and G20 summit meetings, said it was "unlikely" that the missile was fired from Russia, AP also reported.
He pledged his support for the investigation into the incident, and convened an emergency meeting of G7 and NATO leaders in Bali, Indonesia, following news of the strike.
However, Biden said there was "preliminary information" that contests the theory that the missile was fired from within Russia.
He expressed his condolences for the loss of life and reaffirmed the U.S.' "ironclad commitment" to NATO.
While the U.S. and some NATO members have been supplying weapons, ammunition and supplies to Ukraine to help it defend itself against the Russians, and provided training for Ukrainian forces, no NATO personnel have directly taken part in the fighting.
Top image by Artur Widak/Anadolu Agency via Getty Images.