John Demjanjuk, a retired Ohio autoworker who was deported Monday to Germany, is accused of being a guard at a death camp were 29,000 Jews and others were killed.

The Ukrainian-born Demjanjuk says he was a Red Army soldier who was captured by the Nazis, spent the rest of the war as their prisoner and never hurt anyone.

There are Nazi-era documents that suggest otherwise — including a photo ID identifying Demjanjuk as a guard at the Sobibor death camp and saying he was trained at an SS facility for Nazi guards at Trawniki.

Still, the key to the 89-year-old Demjanjuk's fate may not lie with the evidence but rather on a German court's decision about whether he is medically fit to stand trial. In any case, Demjanjuk, who has been without a country since the U.S. stripped him of his citizenship in 2002, is likely to spend the rest of his life in Germany, either in jail or in a home for the elderly.

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Chronology of the John Demjanjuk Case

Questions have been raised about Demjanjuk's health.

Dramatic photos last month showed him wincing in apparent pain as he was removed by immigration agents from his home in Seven Hills, Ohio. However, images taken only days earlier and released by the U.S. government showed him entering his car unaided outside a medical office.

Demjanjuk's son, John Demjanjuk Jr., said Monday that his father is dying of leukemic bone marrow disease and may not even survive the flight from Cleveland to Munich.

Timing is everything in the case, according to Jonathan Drimmer, who served as the lead lawyer in the 2002 U.S. case against Demjanjuk.

"This case is not about the strength of the evidence, it is about how quickly this guy can be put on trial," Drimmer said Monday. "The evidence against him is so strong."

Demjanjuk Jr. said his father was never involved with the Nazis.

"He was a Ukrainian POW nearly killed in combat against the Nazis," he said in an e-mail to The Associated Press Monday.

Throughout three decades of court action in the U.S. and Israel, Demjanjuk has insisted he was an innocent victim.

At his trial in Jerusalem, where he was convicted in 1988 of being the Treblinka death camp guard "Ivan the Terrible," Demjanjuk maintained he was a victim of mistaken identity, insisting he spent most of his time in POW camps as a captured Soviet soldier. At worst, he said he was a driver at Sobibor, according to documents at the International Tracing Center in Bad Arolsen, Germany, which holds the records of millions of people displaced by World War II.

"I felt myself like I was in Sobibor or Treblinka when I was in the (POW) camps," he told the court in Israel.

Demjanjuk was sentenced to hang, but had his conviction thrown out in 1993 by Israel's Supreme Court, which argued he was not conclusively identified as the notorious Treblinka killer.

Drimmer said that U.S. courts have upheld evidence — shared with the German prosecutors — that show Demjanjuk was at Sobibor and Flossenberg.

Among documents obtained by the Munich prosecutors is an SS identity card that features a photo of a young, round-faced Demjanjuk along with his height and weight, and says he worked at Sobibor.

Demjanjuk argued at his trial in Israel that the card, issued at the Trawniki training center for Nazi guards, was forged by the Soviet Union, which provided it to Israel.

"This whole document I have never seen and never signed. I was never at Trawniki," Demjanjuk said.

German prosecutors also have a transfer roster that lists Demjanjuk by his name and birthday and says he was at Sobibor, and statements from former guards who remembered him being there, Drimmer said.

Further, Drimmer cited Demjanjuk's U.S. immigration document, which listed Sobibor as his former place of residence before coming to the U.S. in 1952.

"The odds that you have Nazi wartime documents that put him at Sobibor, that former guards remember him and that he writes that he lived in Sobibor — that he didn't serve at the death camp? It's not remotely possible," Drimmer said.

Any evidence, or trial, will have to overcome Demjanjuk's health. His family says he is virtually immobile, wracked by pain. Recent U.S. government surveillance video showed him walking unassisted.

When Demjanjuk arrives in Munich, he will be taken to the Stadelheim prison for a medical examination, according to his lawyer, Ulrich Busch, who said he expected his client before midday Tuesday.

There he will be visited by a judge to have the 21-page arrest warrant read to him, giving him a chance to respond to the allegations. Only after that can formal charges be pressed and it was not immediately clear when that would happen.

It remains unclear whether Demjanjuk will stay in the prison, which has a medical unit, or be taken to an area hospital, where guards would be posted around the clock.

More than six decades since the end of World War II, bringing alleged Nazi war criminals to trial has become increasingly difficult as the suspects grow increasingly old and frail.

In January, a German court ruled that Heinrich Boere, then 87, was too ill to stand trial for the wartime killings of three Dutch civilians in the Netherlands. Boere was sentenced to death in absentia by a Dutch court in 1949, though the sentence was later commuted to life in prison. He had successfully blocked, through German courts, attempts to extradite him or enforce the verdict here. Authorities are currently seeking a second medical opinion in an appeal of the ruling.

Drimmer said he believes that if Demjanjuk goes to trial in Germany there is sufficient evidence to convict him.

"What we established in our trial was that he says he was in places that are historically impossible," Drimmer said, citing a claim by Demjanjuk that he was in a POW camp at a time when it no longer existed. "Between 1942 and late '44, his alibi simply doesn't work."

Demjanjuk Jr. said Germany is using his father as a pawn to try to atone for the past.

"Given the history of this case and not a shred of evidence that he ever hurt one person let alone murdered anyone anywhere, this is inhuman even if the courts have said it is lawful," Demjanjuk Jr. said.

"This is not justice, it is a vendetta in the falsified name of justice with the hope that somehow Germany will atone for its past," he said.