Germany - Prosecutors accused 89-year-old John Demjanjuk on Tuesday of knowingly herding thousands of Jews to their deaths in the Holocaust and standing by as victims of Nazi death camp Sobibor screamed in fear.

Propped up under a white sheet on a mobile bed, the former U.S. carworker closed his eyes or stared into space as prosecuting lawyers charged him with helping to kill 27,900 Jews in what may be Germany's last major Nazi-era war crimes trial.

Demjanjuk denies he was involved in the Holocaust and his family insists he is too frail to stand trial.

State prosecutor Hans-Joachim Lutz told the court that shortly after he arrived in Sobibor at the latest, Demjanjuk knew the purpose of the camp was to exterminate Jews.

At the same time, he did not escape from the camp, although he had the chance to do so when he was off duty, or on duty outside the camp. He possessed a gun which would have made escape possible, Lutz told the court.

With relatives of the victims looking on, Lutz said that Demjanjuk had been involved in the process of extermination because he had stood by with his gun as Jews were taken off trains, made to undress and pushed into gas chambers.

In the time between March 1943 to mid-September 1943, he, along with others, therefore knowingly ensured that the victims named had no possibility of escape, but were instead put to death in gas chambers or were shot, he added.

He therefore willingly participated in the murders of at least 27,900 people who were brought to Sobibor in the 15 trains from the Netherlands, as well as in other transports.

Shortly after the day's hearing began, Demjanjuk, wearing a black leather jacket, grey top and a baseball cap, began waving his hand in what appeared to be an attempt to form the sign of the cross over his head and shoulders.

The court adjourned briefly after about 80 minutes while Demjanjuk was laid on his side, facing the presiding judge with his head turned away from the rest of the court.

Not long after the break, the judge gave Demjanjuk an opportunity to respond to the charges, but the defendant gave no obvious sign of response. His lawyer, Ulrich Busch, told the court that they had agreed he would not speak at this point.

Although he has acknowledged being at other camps, Demjanjuk has denied he was in Sobibor, which prosecutors say was run by 20-30 Nazi SS members and up to 150 former Soviet war prisoners.

In the Sobibor gas chambers Jews died within 20 to 30 minutes after inhaling a toxic mix of carbon monoxide and carbon dioxide, prosecutors said. Groups of about 80 were forced into gas chambers measuring about 4 by 4 meters.

Screams, cries and banging could be heard from outside as panic gripped the victims, the prosecutors added.

David van Huiden, 78, a Dutch Jew whose family was killed in Sobibor, said anyone working at the camp was responsible.

It is a shame, he said of Demjanjuk.
We here consider him to be doing a bit of theater. On top of that, he isn't facing anybody, his eyes are mostly closed. It is my feeling that the German court is so eager to have him here they will accept him in any shape, he added.

Demjanjuk was born in Ukraine and fought in the Red Army before being captured by the Nazis and recruited as a camp guard. He emigrated to the United States in 1951.

He was extradited to Israel in 1986 and sentenced to death in 1988 after Holocaust survivors said he was the sadistic guard known as Ivan the Terrible at the Treblinka camp where 870,000 people died. The Israeli Supreme Court overturned that conviction in 1993 and freed him after fresh evidence showed another man was probably the Treblinka guard.

In May, he was extradited from the United States where he had lived in a suburb of Cleveland, Ohio.

(Writing by Dave Graham, editing by Paul Taylor)