Berlin's Pilecki Institute, which is dedicated to researching 20th-century history including Nazi crimes in World War Two, is tapping that experience to collect testimonies from refugees about possible war crimes in Ukraine.
The International Criminal Court (ICC) started a formal investigation into possible war crimes and crimes against humanity in Ukraine after Russia invaded on Feb. 24.
The Pilecki Institute, named after a Polish cavalry officer who risked his life to document the situation in the Auschwitz concentration camp during World War Two, said it had started its own initiative to document war crimes through interviews with refugees.
"We are collecting all witness reports about war crimes in Ukraine relying on the experience we have as an institution that normally deals with...the voices of victims of the Second World War," Mateusz Falkowski, deputy head of the institute, told Reuters.
More than 369,000 people fleeing the war in Ukraine have been registered in Germany, Interior Ministry data showed on Friday.
The witness interviews start by asking for a short written description of the witness's own situation during the war and then follow up with questions about specific events at certain places and times.
"For example, what happened on the specific day and in this place, so in Mariupol, Kherson or in other places. Where they were and what they saw exactly," Falkowski said.
The crimes documented range from the destruction of civilian infrastructure or monuments to sexual violence or other war crimes, Falkowski said, adding that the questionnaire was created with the help of legal professionals to ensure the data originated from it is legally relevant after the war.
"That means, scientifically speaking, we're building an archive of oral history," he said.
"I hope that Ukraine will not be forgotten. The hope is that (people in the West)...will remember...if they have the opportunity to rely on these interviews, materials and documents," Falkowski said.
The institute, located within walking distance from Berlin's Holocaust memorial at the heart of the German capital, also collects clothing and medical aid to be packed and sent to Ukraine.
On Friday the U.N.'s human rights office said there was growing evidence of Russian war crimes in Ukraine, including signs of indiscriminate shelling and summary executions, and said Ukraine also appeared to have used weapons with indiscriminate effects.
Russia describes its incursion as a "special military operation" to disarm and "denazify" Ukraine and denies targeting civilians or committing any such war crimes.