I am aware of one instance and, so far, Ukraine has pledged to handle the situation just like the Western nations would handle it. Again, there is a vast difference between ordering or ignoring war crimes (Russia) and punishing rogue elements of your armed forces who commit war crimes.
On Wednesday, the New York Times verified the veracity of a video that appears to show Ukrainian forces executing one Russian prisoner of war and leaving another to die on a road near Kyiv. The revelation puts Ukrainian President Zelensky in a tough spot. He has framed Ukraine’s fight as a struggle for democracy, human rights, and the rule of law. Holding Ukrainian forces accountable for war crimes would be consistent with that.
At the same time, it’s not easy, politically, to prosecute your own soldiers while they are holding off a brutal invasion. What’s more, the large presence of irregular, volunteer fighters on the Ukrainian side could complicate accountability for crimes like this. Asked about the incident on Thursday, Ukraine’s Foreign Minister Dmytro Kuleba
said “the Ukrainian army observes the rules of warfare” and pledged that any “isolated incidents will definitely be investigated."
So far, Ukraine has done the right thing. Meanwhile, the Russian military continues to commit atrocities.