Ukraine is investigating more than 25,000 suspected war crimes since the Russian invasion five months ago.
Yuriy Bilousov, head of the prosecutor’s war crimes division, said 135 people have already been charged, although only 15 of them are now in custody and 120 are still in custody.
He told Reuters news agency that 13 cases have been submitted to courts and seven sentences have been handed down since the Feb. 24 invasion by Vladimir Putin.
In May, a 21-year-old captured Russian soldier became the first person to be convicted in a war crimes trial in Ukraine. He was sentenced to life in prison for killing an unarmed civilian.
“We have sometimes been asked why we persecute such … low-ranking officers. It’s just because they are physically here,” Bilousov said.
“If generals were here physically and we could arrest” [them]we would certainly persecute generals.”
Reports suggested that many civilians had been left dead on the streets in Bucha, some with their hands tied, and satellite images revealed what appeared to be a mass grave in the city.
US President Joe Biden has branded Putin as a “war criminal” and Ukrainian President Volodymyr Zelensky called the situation in Bucha an act of genocide.
The first independent investigation into allegations of Russian violations of humanitarian law in Ukraine, published in April, revealed evidence of multiple war crimes.
The preliminary report from the Organization for Security and Cooperation (OSCE) in Europe found that the bombing of a children’s hospital and theater in the besieged port city of Mariupol amounted to war crimes, as did the forced removal of thousands of Ukrainians to Russia.
Investigators said there were “credible reports” that civilians were being held by Russian forces and subjected to ill-treatment amounting to torture.