AMSTERDAM  –  A painting stolen from a Jewish art collector by the Nazis during World War Two has been found in the home of descendants of a notorious Dutch SS collaborator, an art detective has said. Portrait of a Young Girl, by Dutch artist Toon Kelder, is believed to have hung for decades in the home of Hendrik Seyffardt’s family, Arthur Brand said. It had belonged to Jewish art dealer Jacques Goudstikker, who died while fleeing the Nazi invasion of the Netherlands in 1940, leaving behind a collection of more than 1,000 paintings. The case was brought to Brand’s attention by a man who told him he was a descendant of Seyffardt and that he was “disgusted” to learn his family had kept the artwork for years. Seyffardt was a Dutch general who commanded a Waffen-SS unit of volunteers on the eastern front before he was assassinated by resistance fighters in 1943.  Shortly after learning he was related to the Nazi collaborator, the man approached his grandmother to ask about the painting’s history. She is said to have told him it had been purchased during World War Two and that it was “Jewish looted art, stolen from Goudstikker. It is unsellable. Don’t tell anyone.” The family, which changed their name at the end of the war, have admitted being in possession of the painting but denied knowing its true origin, according to a statement to Dutch media. After learning of the painting’s history, the family member contacted Brand through an intermediary, believing the only way for it to be returned was for the story to be made public. The family member told Dutch outlet De Telegraaf: “I feel ashamed. The painting should be returned to the heirs of Goudstikker.”  In a statement to the same newspaper, his grandmother said: “I received it from my mother. “Now that you confront me like this, I understand that Goudstikker’s heirs want the painting back. I didn’t know that.” Upon being informed of the painting’s existence, Brand launched his own investigation. He discovered the painting had a label on the back and the number 92 etched into its frame. Brand then searched the archives of a 1940 auction where much of Goudstikker’s looted collection was sold and discovered an item under the number 92 titled “Portrait of a Young Girl” by Toon Kelder.  Brand believes the painting had been plundered by Hermann Goering, one of the most powerful figures in the Nazi Party, when Goudstikker fled for Britain in 1940. It was then sold to Seyffardt at auction before being handed down to his descendant, Brand says. After launching his investigation, Brand contacted the lawyers of Goudstikker’s heirs, who he said confirmed the collector had previously owned six paintings by Toon Kelder.  He added that the lawyers also confirmed to him these paintings had been included in the 1940 auction where Brand believes Portrait of a Young Girl had been sold.  Brand told the BBC that the discovery was “stunning”, describing it as “the most bizarre case of my entire career”. He added that, if the painting were to be put on sale, it could fetch a hefty price. “Such paintings could been sold anywhere between thousands and tens of thousands,” Brand said.