Mr Demjanjuk says he was a prisoner of war of the Nazis during World War II
The alleged Nazi war criminal, John Demjanjuk, has been transferred from prison in Germany to hospital after developing gout, his lawyer has said.
Mr Demjanjuk was moved from Stadelheim prison in Munich on Sunday for treatment of the joint disease.
The 89-year-old was deported from the United States to Germany earlier this month after a long extradition battle.
He has denied accusations that he was a guard at the Sobibor death camp and an accessory to the murder of 29,000 Jews.
Mr Demjanjuk says he was captured by Germans in his native Ukraine while fighting for the Red Army and kept as a prisoner of war.
Prosecutors, however, say they have documents that prove his collaboration with the Nazis, including a Waffen SS identity card showing he was a Wachmann (guard) at Sobibor in 1943 and many witness testimonies.
Mr Demjanjuk's lawyer said he had been admitted to Harlaching clinic on Sunday after suffering from gout, but that he was expected to return to the medical unit at Stadelheim later on Tuesday.
Doctors are assessing whether Mr Demjanjuk is fit to stand trial
"It was determined that his blood was not as it should be," Guenther Maull told the Associated Press.
Gout is a joint disease caused by a problem with a person's metabolism that leads to high levels of uric acid in the blood.
Mr Demjanjuk's son, John, meanwhile told AP that he had heard his father was suffering from low haemoglobin levels and "severe pains from other conditions", but that he had not been permitted to contact him.
Prosecutors and doctors at Stadelheim are still assessing whether he is fit to stand trial. Mr Maull said he did not know when a decision would come.
On 13 May, a day after he was deported, they declared him healthy enough to remain in custody until a decision was made.
At the time, the prison's deputy director, Jochen Menzel, said Mr Demjanjuk was "in better shape than usual for an 89-year-old".
His lawyers had told US courts he was too frail to be deported.