The brutal images of Butja, with dead civilians on the streets, which are now spreading around the world, are condemned by those in power and leaders.
Experts believe that this may be the worst type of war crime.
- I am, like everyone else, completely shocked, says Philippe Sands, British lawyer and expert on international law, to SVT's Agenda.
- The killing seems to be targeted and it appears to be war crimes.
It can even be so systematic that it can be classified as a crime against humanity.
It remains to be determined, but these are shocking images from the heart of Europe in our time, he says.
Want to see special war crimes tribunal
Philippe Sands wants to see a special war crimes tribunal for Ukraine.
He points to the importance of investigating aggression crimes, what in Nuremberg were called crimes against peace, a crime that the ICC has no jurisdiction to judge.
"It is the only crime that will surely lead to the top, directly to Putin," he said.
In the video, Philippe Sands talks more about the possibilities of bringing Putin to justice.