Polish experts have confirmed that a missile that killed two people at a grain facility in November was fired by Ukraine, the Rzeczpospolita daily reported, citing sources.

The explosion of the missile in NATO-member Poland fuelled fears that the war in Ukraine could spiral into a wider conflict by triggering the alliance’s mutual defense clause, but at the time Warsaw and NATO said that they believed that it was a Ukrainian projectile that had strayed off course.

Sources with knowledge of the investigation told Rzeczpospolita that Poland had established that the missile that landed in the village of Przewodow was an S 300 5-W-55 air-defense missile.