BERLIN — John Demjanjuk is fit enough to remain in custody at Germany's Stadelheim prison, officials said today.

Demjanjuk is being held on suspicion of acting as an accessory to the murder of 29,000 people at a Nazi death camp and doctors at Stadelheim found him fit enough to remain in detention there, the prison said.

Had he been unwell, the 89-year-old retired autoworker could have been transferred to a hospital.

Anton Winkler, a spokesman for Munich prosecutors, said Demjanjuk "did fine" during his first night in prison and was doing well under the circumstances.

"There were no problems whatsoever," Winkler said. "He is still fit enough to remain in custody."

Munich prosecutors must still determine whether the former Ohio resident, who was flown to Germany aboard a private jet Tuesday, is fit enough to stand trial. But it could take up to two weeks for an expert to observe him and make a recommendation.