Convicted Nazi war criminal John Demjanjuk's bid to regain his U.S. citizenship was denied Tuesday by a judge who said he had lied about where he was during World War II.

U.S. District Judge Dan Aaron Polster rejected the retired autoworker's citizenship claim, which was based on newly discovered documents, including one suggesting an incriminating document was a Soviet fraud.

"John Demjanjuk has admitted that he willfully lied about his whereabouts during the war on his visa and immigration applications to gain entry to the United States," the judge wrote. "Despite numerous opportunities, Demjanjuk has never provided a single, consistent accounting of his whereabouts during the war years 1942 to 1945."

Demjanjuk was convicted by a German court that found he had served as a guard at the Nazis' Sobibor death camp in occupied Poland. He was sentenced to five years in prison.

Demjanjuk, who's in his 90s, has been in poor health for years and has been in and out of a hospital since his conviction.

His lawyers argued that the government failed to disclose important evidence, including a 1985 secret FBI report uncovered by The Associated Press that indicates the FBI believed a Nazi ID card purportedly showing that he served as a death camp guard was a Soviet-made fake.

Federal authorities had said Demjanjuk, who has denied serving as a guard at any Nazi camp and is free on bail, was trying to cast himself as a victim following his conviction in Germany on more than 28,000 counts of accessory to murder.

In a response to the original defense citizenship filing, the government included an Oct. 12 affidavit from retired FBI agent Thomas Martin. He said the March 4, 1985, report written by him was based on speculation about a Soviet forgery, not any investigation.

Demjanjuk cannot leave Germany because he has no passport after being stripped of his U.S. citizenship ahead of his deportation to Germany in 2009. He could have gotten a U.S. passport if the denaturalization ruling had been overturned.

The Ukrainian-born Demjanjuk was a Soviet Red Army soldier captured by the Germans in 1942. The Munich court found he agreed to serve the Nazis as a guard at Sobibor.

Demjanjuk's public defender, Dennis Terez, would not comment on a possible appeal of the citizenship ruling but said, "We're evaluating our various options at this point."

Mike Tobin, a spokesman for the U.S. attorney's office in Cleveland, said prosecutors were pleased with the ruling.

"All along the issue in this specific aspect of the case was really just the uninformed or misinformed speculation of one FBI agent, as I think the ruling makes clear," he said.

Demjanjuk's son, John Demjanjuk Jr., who has spoken often on his father's behalf, could not be reached for comment Tuesday. Email and phone messages were left for him.