Poland is deploying army units to the border with Ukraine — Reuters

Defense Minister Władysław Kosiniak-Kamysz announced that the Polish army would support border guards and is reinforcing border security to that end.

It is reported that a Polish army engineering regiment is constructing defensive infrastructure, and observation and security posts are being set up near the Dorohusk, Medyka, and Korczowa border crossings. 

 “The past few days have shown that Russia's actions threaten the security of all of Europe,” Kosiniak-Kamysz said. He added that the government had decided to strengthen infrastructure used by border authorities.

 The measures follow a series of Russian attacks on western Ukraine, which Polish officials say could be aimed at disrupting the supply of military assistance entering Ukraine through neighboring countries.