The UK is "seeking clarity" after reports Russian missiles crossed into Poland, killing two people.
Reports began to surface on Tuesday (November 15) evening after a senior US intelligence official said Russian missiles had struck Przewodow, a village in eastern Poland near the border with Ukraine. The Polish Government confirmed an explosion in the village killed two people.
Polish Prime Minister Mateusz Morawiecki called an urgent meeting to discuss national security, a government spokesman said on Twitter. A spokesperson from the government spoke to journalists in Warsaw after the meeting and confirmed they are "raising the readiness of military units" and verifying if they need to activate NATO Article 4.
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That article says: "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."
A UK Foreign Office spokesman said: "We are investigating these reports and liaising closely with allies."
Jens Stoltenberg, the secretary general of NATO said the alliance is "monitoring the situation in Poland," adding that "allies are closely consulting".
Mr Stoltenberg added: "Spoke with President Duda about the explosion in Poland. I offered my condolences for the loss of life. NATO is monitoring the situation and Allies are closely consulting. Important that all facts are established."
Russia's defence ministry said reports of Russian involvement were a "deliberate provocation aimed at escalating
the situation".
It added in a statement: "No strikes on targets near the Ukrainian-Polish state border were made by Russian means of destruction."
However, Moscow launched a large number of missiles at Ukraine on Tuesday, knocking out power for seven million households. Some of the missiles hit Lviv in western Ukraine, which is only 50 miles from the Polish border.
A number of NATO allies have voiced their support for Poland including Estonia, Latvia, Lithuania, Czech Republic and Slovakia.
European Council President Charles Michel said: "Shocked by the news of a missile or other ammunition having killed people on Polish territory. My condolences to the families. We stand with Poland. I am in contact with Polish authorities, members of the European Council and other allies."
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