The Simon Wiesenthal Center filed a lawsuit Wednesday asking Berlin prosecutors to investigate whether the family or attorneys of Nazi war criminal Aribert Heim have lied about whether he was dead or alive. The SS doctor's son, Ruediger Heim, claimed in a February television interview that his father died in 1992 in Cairo. But Efraim Zuroff, the top Nazi hunter at the Simon Wiesenthal Center, said Heim's attorney recently claimed in a tax case in Berlin that there was still regular contact with the doctor, who would be 94 if he is alive. "If that is the case, then someone is lying - either this guy committed perjury on behalf of his client, Dr. Aribert Heim, or Ruediger Heim," Zuroff told The Associated Press in a telephone interview from Jerusalem. The Wiesenthal Center cited a copy of a 2001 ruling that it had obtained in which 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." But the attorney who argued the case, Berlin's Michael Hoepfner, said he had never made such a claim in the court, and that Steinacker had told him that he had not heard from Heim for decades. "I only argued before the court that if one is not declared dead, then he legally has to be considered alive," Hoepfner told the AP. Reached at his office in Frankfurt, Steinacker said he was granted power-of-attorney over Heim's estate in May 1962, and has represented him in tax cases. But Steinacker said that he has never asserted to have been in contact with Heim for nearly four decades. "That is entirely false," Steinacker said. "I have no contact with Mr. Heim." Michael Grunwald, spokesman for the Berlin prosecutor's office, said that he could not yet confirm his office had received the Wiesenthal Center's suit, and that it could take some time to evaluate whether there was enough evidence to open an investigation. 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. They are currently being examined by experts trying to determine their authenticity in a process that could still take "quite a while" longer, spokesman Horst Haug 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." Haug's office has asked permission to send investigators to look for the body, but he said Wednesday they were still awaiting an answer from Egyptian authorities. The tax case centers around about â‚¬1 million in a Berlin bank account that belongs to Heim, according to the Wiesenthal Center. 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, Hoepfner said. In 1999, the tax authorities questioned the repayments, saying they needed proof that Heim was not living in Germany. The account is overseen by a state-appointed administrator, which contracted Hoepfner to argue the case, which has been in court at least a half dozen times as recently as this week, Hoepfner said. It was not clear when it might be resolved.