An Israeli court today sentenced John Demjanjuk to be executed for war crimes committed as ``Ivan the Terrible,'' a sadistic Nazi guard who ran gas chambers where about 800,000 Jews died. ``He was a chief hangman who with his own hands killed tens of thousands with cruelty ... We sentence him to death,'' said Judge Zvi Tal. Onlookers clapped and shouted as the sentence was announced. Some chanted ``Bravo.'' Others shouted: ``Death, death.'' Last week, the court convicted the 68-year-old retired Ohio autoworker of Nazi war crimes. It said he was responsible for the deaths of thousands of Jews at the Treblinka concentration camp in Nazi-occupied Poland. About 800,000 Jews died in 1942 and 1943, when ``Ivan'' worked at the camp. Only one man has ever been executed in Israel's 40-year history. Adolf Eichmann, architect of the Holocaust, was hanged in 1962. Court Spokesman Yossi Hassin said Demjanjuk would most likely be hanged. ``If the sentence is upheld on appeal, the expectation is he would be hanged,'' Hassin said. Demjanjuk attended today's sentences in a wheelchair, complaining of back problems. He entered the courtroom moments before the verdict was read, shouting in Hebrew: ``I am innocent.'' A Christian, he was seen making the sign of the cross and whispering to himself, apparently praying, during arguments from prosecutors who demanded the death penalty. After the verdict he was wheeled away, expressionless and ringed by riot police. Demjanjuk's lawyers have said they will appeal his conviction to the Supreme Court. Today's sentence followed a trial that lasted 14 months. Yosef Czarny, a Treblinka survivor who testified against Demjanjuk, said that although ``a thousand deaths cannot compensate for what happened ... at least we have judged one of the Angels of Death.'' ``I feel like a burden has been lifted,'' said Pinchas Epstein, another Holocaust survivor. Tal's statement after three hours of judicial deliberation drew applause and whistling from hundreds of Israelis in the audience, including survivors of the Holocaust. Several hundred onlookers crowded into the converted movie theater to hear the verdict. Earlier, longtime observers said they expected the death penalty because of the sweeping guilty verdict which discounted each defense argument. ``There is no forgiveness in the law or the heart ... (Holocaust) victims are still crying out to us,'' said Tal, who was born in Poland. ``Even a thousand deaths cannot compensate.'' Demjanjuk's son, 22-year-old John Jr., said his family had expected a death sentence. ``It amounts to nothing less than the judicial murder of an innocent man,'' he said. ``It will bring shame to the state of Israel, the Israeli Justice Department, the U.S. Justice Department, and most unfortunately the six million victims of the Nazi Holocaust.'' Earlier in the day, his father told the three-judge panel it was making a ``very, very, very big mistake.'' The Ukrainian-born Demjanjuk has consistently alleged he is a victim of mistaken identity, although he admitted lying on his American emigration papers about his past. He contends he was held in a Nazi prisoner of war camp during the critical period in question. ``I am not Ivan the Terrible, and to that God is the most just witness. He knows I am innocent,'' Demjanjuk told the court today. He spoke in Ukrainian. The court adjourned briefly after Demjanjuk spoke to allow the judges time to consider the arguments. The defense also had pleaded against a death sentence. ``There is also a question of an individual's holocaust,'' said defense attorney John Gill of Cleveland. ``The taking of any innocent human life is a holocaust.'' Opening the proceedings today, prosecutor Yona Blattman told the three judges that Demjanjuk ``was not a small cog in the Nazi machine, he was a major criminal, an arch-henchman.'' ``We maintain the only punishment that can be imposed on the accused is the death penalty,'' Blattman argued. Demjanjuk pointed to his chest, shaking his head no, as Blattman alleged that Demjanjuk had ``distinguished himself by the sheer brutality of his behavior ... beating Jews mercilessly with a sword or whip.'' Gill said the conviction could be shown at a later date to have been incorrect and he cited previous wrongful convictions. The problem with the death penalty, he said, is that it ``is in fact irrevocable.'' In its verdict last week, the tribunal convicted Demjanjuk ``without hesitation or doubt'' of being the brutal guard at Treblinka. The three judges said Demjanjuk ``killed masses of human beings with his own hands,'' frequently exceeding the brutality ordered by Nazi commanders. Nazi war crimes and terrorism are the only offenses punishable by death in the Jewish state. During the trial, five Holocaust survivors identified Demjanjuk, of suburban Cleveland, as the Nazi guard who operated Treblinka's gas chambers. Justice Minister Avraham Sharir had urged the death penalty for Demjanjuk, saying ``a man convicted of such terrible crimes deserves no other sentence.''