Germany's highest criminal court must decide where a former Nazi death camp guard — now a U.S. resident — can be prosecuted for alleged involvement in the deaths of 29,000 Jews, a prosecutor said Friday.

The German federal office that pursues Nazi-era crimes asked Munich prosecutors in early November to take the case against John Demjanjuk and request his extradition from the United States.

But Munich prosecutor Christian Schmidt-Sommerfeld said the case has now been referred back to the federal office, to be taken to the Federal Court of Justice, after Munich decided that it was not clear who had jurisdiction.

Schmidt-Sommerfeld said Munich prosecutors felt it was better to resolve all issues now rather than risk having a case collapse later because of jurisdictional issues.

"It has not been decided that we are not responsible, but ... it is not 100 percent certain," he said.

He said he hoped a decision would be made before the end of the year.

Demjanjuk, a retired autoworker who emigrated to the United States in 1952, denies involvement in war crimes, saying he served in the Soviet army and became a prisoner of war when he was captured by Germany in 1942.

But a U.S. District judge ruled in 2002 that Demjanjuk had served at several Nazi death camps during World War II. Demjanjuk's identification card number was traced to each posting, the government said.

German prosecutors have said Demjanjuk was a guard for seven months at the Sobibor death camp, in Nazi-occupied Poland, and they plan to use transport lists of prisoners that arrived at the camp during his tenure there as evidence of his alleged involvement in their deaths.

A native of Ukraine who settled in suburban Cleveland, Demjanjuk was extradited to Israel in 1986, when the U.S. Justice Department believed he was the sadistic Nazi guard known as Ivan the Terrible at the Treblinka death camp.

He spent seven years in custody before the Israeli high court freed him after receiving evidence that another Ukrainian, not Demjanjuk, was that Nazi guard.

But when he returned to the United States, the Justice Department again sought to revoke his citizenship, alleging that he had been a guard at Nazi death and forced-labor camps.

A December 2005 ruling determined that he could be deported to his native Ukraine or to Germany or Poland, but Demjanjuk spent several years challenging that ruling.

On May 19, the U.S. Supreme Court chose not to consider Demjanjuk's appeal against deportation.