A researcher who stumbled across a World War II-era letter from the director of a French medical facility made a grisly discovery based on that letter: the remains of Jewish gas-chamber victims who had been experimented on by Nazi anatomist August Hirt, the AP reports. Historian Raphael Toledano rediscovered the remains—believed to be from some of the 86 Holocaust victims acquired by Hirt in 1943 after their executions at the Natzweiler-Struthof concentration camp, the Jerusalem Post notes—in the Strasbourg Medical Institute's closed collection. The gruesome discoveries included "a jar containing skin fragments of a gas chamber victim," as well as test tubes with intestines and a stomach, per the AFP. The bodies had originally been found in 1944 after Strasbourg was freed from the Nazis. Some of the bodies were intact, some burned and dismembered—but it had been believed they were buried in a common grave in 1946, AFP reports.
Not all the remains, apparently; AFP suggests it wasn't Hirt who had preserved the newly found remains, but a Strasbourg employee who had been told to carry out "judicial autopsies" of the victims after their 1944 discovery. The letter "mentioned the jars containing the samples taken in the course" of those autopsies. "This discovery raises serious questions about who knew about these remains and why they did not reveal this sooner," a spokesman for the Board of Deputies of British Jews says, per the Daily Mail, adding that a full investigation is warranted. Hirt killed himself in 1945 before he could be brought to Nuremberg for trial. Authorities say they'll return the victims' remains to Strasbourg's Jewish community. (In other WWII-related news, a German man has uncovered Nazi-era treasure.)