BERLIN - Germany has launched a war crimes investigation against an 87-year-old Philadelphia man it accuses of serving as an SS guard at the Auschwitz death camp, The Associated Press has learned, following years of failed U.S. Justice Department efforts to have the man stripped of his American citizenship and deported.

Johann "Hans" Breyer, a retired toolmaker, admits he was a guard at Auschwitz during World War II, but told the AP he was stationed outside the facility and had nothing to do with the wholesale slaughter of some 1.5 million Jews and others behind the gates.

The special German office that investigates Nazi war crimes has recommended that prosecutors charge him with accessory to murder and extradite him to Germany for trial on suspicion of involvement in the killing of at least 344,000 Jews at the Auschwitz-Birkenau death camp in occupied Poland.

The AP also has obtained documents that raise doubts about Breyer's testimony about the timing of his departure from Auschwitz.

The case is being pursued on the same legal theory used to prosecute late Ohio autoworker John Demjanjuk, who died in March while appealing his conviction in Germany on charges he served as a guard at the notorious Sobibor death camp, also in occupied Poland.

Prosecutors maintain they can use the same legal argument to pursue Breyer. Under that line of thinking - even without proof of participation in any specific crime - a person who served as a death camp guard can be charged with accessory to murder because the camp's sole function was to kill people.

Authorities in the Bavarian town of Weiden, who have jurisdiction, are currently trying to determine if the evidence is sufficient for prosecution. For more than a decade, the Justice Department waged court battles to try to have Breyer deported. That legal saga ended in 2003, with a ruling that allowed him to stay in the United States, mainly on the grounds that he had joined the SS as a minor and could therefore not be held legally responsible for participation in it.

Breyer testified in U.S. court that he served as a perimeter guard at Auschwitz I, but denied ever serving in Auschwitz-Birkenau, the death camp area where the bulk of the people were killed. He also said he deserted in August, 1944 and never returned to the camp.

A U.S. Army intelligence file on Breyer, obtained by the AP, calls that statement into question.