Horst Wächter, the 78-year-old son of a notorious SS general, has returned artworks taken decades ago by his parents from a museum collection in Poland. On Sunday, he attended a ceremony in Kraków at which three stolen works were returned to the Polish government, reports the Guardian. The works are among half a million pieces estimated to have been looted from Poland by Nazi or Soviet forces during World War II.

“This is probably the first time that the member of a family of one of the most important Nazi occupiers is giving back art that was stolen from Poland during the war,” said Ryszard Czarnecki, a vice-president of the European parliament and a member of the Polish Law and Justice party.

Wächter returned a painting of the Potocki Palace, a map of 17th-century Poland, and an engraving of Kraków during the Renaissance that his mother had stolen from the National Museum in Kraków in 1939. His mother plundered the museum to personally furnish the Potocki Palace, then-headquarters for her husband who was the Nazi governor of Kraków, SS Gruppenführer Otto Wächter.