German investigators say they want to search in Egypt for definitive proof of Aribert Heim's death and are preparing a request to Egypt for permission, the Associated Press said. In a report yesterday, the agency said: "Nazi hunters urged Egypt on Friday to come clean about how much it knew about a fugitive dubbed 'Dr. Death' who reportedly lived here for decades until he died in 1992. But Egypt has long kept a strict silence about former Nazis reported to have taken refuge on its soil." The Austrian-born Heim, a former concentration camp doctor, was accused of carrying out gruesome and deadly experiments on Jewish prisoners. A number of Nazis are believed to have been welcomed in the 1950s by the Egyptian regime of then-President Gamal Abdel-Nasser, who was locked in an intense rivalry with Israel that erupted into wars in 1956 and 1967. So far there is no indication that Heim played any role with the Egyptian government. One current security official would say only that if Heim was in Egypt, he was let in under a previous government. The official, speaking on condition of anonymity because of the sensitivity of the issue, said Egypt would look into the reports. Rafael Medoff, director of the David S. Wyman Institute for Holocaust Studies in Washington, said Cairo should start accounting for Nazis it harbored. "In the 1950s, Egypt opened its doors wide to fugitive Nazi war criminals," he said in an e-mail interview with the AP. "The time has come for Egypt to give a full accounting of its policy of sheltering Nazi war criminals - and if any of those Nazis are still alive, they should be surrendered for prosecution."