The angel of death is smiling ironically. On Saturday morning, John Demjanjuk was found dead in his room in the old-age home in the picturesque town of Bad Feilnbach in southern Germany. While awaiting his appeal to the German court, which sentenced him to five years in prison for the murder of 28,000 Jews, he died a "natural death," at the age of 91.

According to reports Saturday, Demjanjuk will be buried in Germany, which will have to bear the cost of his interment. Demjanjuk carried his greatest secret into the next world. Even after two lengthy trials and a conviction of mass murder, the questions of who he really was, the precise nature of his crimes and where they were committed, remain unanswered.

No living person can say they personally remember seeing him commit the crimes attributed to him. Whether he committed murder with his own hands, was "only" an accessory to murder - whether he stood by and watched the horrors without batting an eye - these are charges for which he will now have to answer a higher authority.

Whether he was "Ivan the Terrible" from Treblinka, as could not be proven in an Israeli court, or a guard at Sobibor death camp, as the German court determined, Demjanjuk was a great riddle and an even greater headache for legal and judicial authorities in three countries: the United States - to which he fled after the Holocaust; Israel - where he was first sentenced to death and subsequently acquitted because of reasonable doubt; and Germany, where he died on Saturday.

"He was small-fry, the lowest rank in the German Nazi hierarchy. But from the point of view of my clients, who lost their families at Sobibor, anyone who took part in the murder, even small-fry, must answer for it," Prof. Cornelius Nestler of Cologne University in Germany, told Haaretz recently. Nestler has in recent years been the lead counsel representing the families of the victims in the trial taking place in Germany.

Last year Demjanjuk was convicted of being an accessory to the murder of 28,000 people in Sobibor death camp in Poland, where he served as a guard from March to September 1943. Between 170,000 and 250,000 Jews were murdered at Sobibor, on the Polish-Ukraine border. At the height of its operation, more than 2,000 Jews a day were killed in its gas chambers.

Demjanjuk was sentenced to five years in prison for his role in the death machine at Sobibor. But the months since then he spent free and unsupervised in an old-age home near Munich, pending appeal. A ruling in his case was to have been issued in a few months.

His death saved Germany the cost of his incarceration and of the sight of a sick and bitter old man being brought to prison on a gurney. "I'm not surprised he died; he was almost 92. But my clients achieved what they sought: the determination that he was an accessory to the murder of their parents and siblings," Nestler told Haaretz. "Now there is no ruling on the appeal, but in any case it did not have a chance. The evidence was clear," he added.

Not everyone agrees with him. Demjanjuk's son, John Demjanjuk, Jr., said on Saturday that his father had been "a victim and survivor of Soviet and German brutality since childhood.

"History will show Germany used him as a scapegoat to blame helpless Ukrainian POWs for the deeds of Nazi Germans," Demjanjuk, Jr. said.

Demjanjuk's trial set an important precedent: He was convicted without eye witnesses to his crimes. The court convicted him of being an accessory to murder based on his service at Sobibor. Hundreds of old investigations against former concentration and death camp guards were reopened. Dr. Efraim Zuroff, the Wiesenthal Center's leading Nazi hunter, said suspects previously immune to trial may now be sought out.

Nestler has submitted to the German authorities a new list of Germans suspected of being camp guards. So far, nothing has been done to locate them. "It's not a matter of lack of will, it's a matter of lack of resources," he told Haaretz. (Additional reporting from AP )