Two years after Russia’s full-scale invasion of Ukraine, United Nations investigators say they have uncovered new evidence of systematic and widespread torture of Ukrainian prisoners held by Russian security forces.

A United Nations Commission of Inquiry on Friday detailed a range of what it described as Russian war crimes, including summary executions, sexual violence and forced transfer of Ukrainian children into Russia. The commission paid special attention to “horrific” treatment of Ukrainian prisoners by Russian security services at detention centers in Russia and occupied Ukraine.

The commission will deliver a report to the Human Rights Council in Geneva next week, detailing accounts of torture from four locations in Russia and seven in occupied Ukraine, strengthening previous findings that the use of torture had become widespread and systematic.

“We are concerned at the scale, continuation and gravity of violations and crimes that the commission has investigated and the impact on victims,“ Erik Mose, chairman of the three-person panel, said in a statement.

“Victims’ accounts disclose relentless, brutal treatment inflicting severe pain and suffering for almost the entire duration of their detention,” the commission said, adding that this resulted in long-lasting physical and mental trauma.

The commission, set up in 2022, said it had previously expressed concern over arbitrary arrest and ill treatment by Ukrainian authorities of people suspected of collaborating with Russian authorities. But in this report, its fifth, the commission recounted only two new cases of Ukrainian aggression, in addition to three previously reported ones.