The Simon Wiesenthal Center is appealing a Berlin prosecutors' office decision to drop an investigation into whether the family or attorneys of Nazi war criminal Aribert Heim lied about whether he was dead, the agency's top Nazi-hunter said Wednesday. The SS concentration camp doctor's son, Ruediger Heim, claimed in a February television interview that his father died in 1992 in Cairo. But in 2001 Heim's attorneys told a court that they were still in regular contact with him. The Wiesenthal Center in March asked prosecutors in Berlin to investigate the discrepancy, but in a June 5 letter to Efraim Zuroff, director of the center in Jerusalem, the office said the case had been shelved. The prosecutors' office said the court remarks from Heim's attorneys were not witness statements, so there was no perjury case to be pursued, and that there were "many statements" over the past decades - including unconfirmed sightings - that indicate Heim could be alive. The Wiesenthal Center filed an appeal Tuesday to Berlin's attorney general, asking for the decision to be reconsidered, Zuroff told The AP in a telephone interview from Jerusalem. "We think the decision is really ludicrous, frankly," he said. "This is an opportunity to provide some clarity on whether or not Heim actually died in Cairo, or if he was still alive in 2001." Heim, who will be 95 this month if he is still alive, was the Wiesenthal Center's most-wanted Nazi war criminal for years before being placed into a special category by Zuroff in April after the reports of his possible death surfaced. Heim was a doctor at the Mauthausen concentration camp in Austria in October and November 1941. Witnesses have said he was involved in gruesome experiments, such as injecting various solutions into Jewish prisoners' hearts to see which killed them the fastest. In early February, the German television station ZDF and The New York Times reported that they had found documents in a Cairo hotel, where Heim allegedly lived out the final years of his life before dying of intestinal cancer, indicating that the notorious doctor had died in the city in 1992. The papers - personal musings, official documents and other items that allegedly belonged to Heim - have been turned over to the Baden Wuerttemberg state police office that has led the manhunt for the former Nazi for decades. The process of trying to determine their authenticity is still ongoing, spokesman Ulrich Heffner said. At the time ZDF reported on the documents, the television station quoted Ruediger Heim as confirming the pseudonym Tarek Hussein Farid as his father's assumed name and the documents as belonging to him. Heim said he visited his father regularly in Cairo and had taken care of him after an operation related to his cancer in 1990. ZDF reported that Heim was buried in a cemetery for the poor in Cairo, where graves are reused after several years "so that the chance of finding remains is unlikely." Heffner's office has been trying to get permission to come to Egypt to look for the body themselves, and also to help determine the authenticity of the documents, but have not yet heard back from Egyptian authorities. The 2001 statement by Heim's attorneys came in a tax case centered around some â‚¬1 million in a Berlin bank account that belongs to Heim. Each year up until 1998, Heim was taxed on the interest made by the money, but then German finance authorities returned the funds to his account because he had been declared as living permanently abroad. In 1999, the tax authorities questioned the repayments, saying they needed proof that Heim was not living in Germany. In a 2001 ruling, the judges wrote that "according to the testimony of the attorney of Dr. Heim ... the holder of Heim's power of attorney Dr. (Fritz) Steinacker has regular contact with Dr. Heim, who is abroad." The attorney who argued the case, Berlin's Michael Hoepfner, has said he never made such a claim in the court, while Steinacker told the AP that he had not had been in contact with Heim for nearly four decades.