A Jewish human rights group urged Serbian authorities Friday to cancel a rock concert at the site of a World War II Nazi death camp. The British band Kosheen is scheduled to hold the concert Saturday at the site of the Sajmiste camp near the center of Belgrade where 48,000 Jews, Serbs and Gypsies perished in the 1940s. In a statement, Efraim Zuroff, the Simon Wiesenthal Center's chief Nazi hunter, called the planned concert "a heartless insult to the memory of the victims of the Nazis." Zuroff noted that Serbian President Boris Tadic had recently expressed a desire to turn the grounds into a museum dedicated to the Holocaust, a proposal the center "warmly supported." "The rock concert scheduled for tomorrow clearly shows how necessary the memorial project conceived by President Tadic truly is," Zuroff said. "We want to remind the authorities in Belgrade that until the museum is completed, the honor and dignity of the victims of Sajmiste must be preserved and rock concerts on the site are not appropriate."