US President Joe Biden said on Tuesday that the missile which killed two in Poland “probably” had not been fired by Russian troops, as part of its war in Ukraine. 

The explosion on Tuesday at a grain facility adjacent to the Ukrainian border came as Russia unleashed a number of missiles to hit Ukrainian energy infrastructure.

According to US officials, initial findings suggested that the missile was fired by Ukrainian forces at an incoming Russian missile, the Associated Press said.

Earlier, Polish President Andrzej Duda had told reporters it was "most likely a Russian-made missile", but he said there was no concrete evidence.