BERLIN — A 93-year-old man has been charged with 300,000 counts of accessory to murder for serving as an SS guard at the Nazis' Auschwitz death camp, prosecutors said Monday.

Oskar Groening is accused of helping operate the death camp in occupied Poland between May and June 1944, when some 425,000 Jews from Hungary were brought there and at least 300,000 almost immediately gassed to death.

In his job dealing with the belongings stolen from camp victims, prosecutors said among other things he was charged with helping collect and tally money that was found.

"He helped the Nazi regime benefit economically, and supported the systematic killings," state prosecutors in the city of Hannover said in a statement.

Groening's attorney, Hans Holtermann, declined to comment on the charges.

Groening himself has openly talked about his time as a guard and said while he witnessed horrific atrocities, he didn't commit any crimes himself.

In 2005, he told Der Spiegel magazine he recalled one incident on "ramp duty" when he heard a baby crying. "I saw another SS soldier grab the baby by the legs ..." he said. "He smashed the baby's head against the iron side of a truck until it was silent."

He has maintained his innocence, however. "Accomplice would almost be too much for me. I would describe my role as a small cog in the gears," he told Der Spiegel. "If you can describe that as guilt, then I am guilty, but not voluntarily. Legally speaking, I am innocent."

Groening, who lives in the Hannover area, is one of some 30 former Auschwitz guards who federal investigators recommended last year that state prosecutors pursue charges against under a new precedent in German law.

Groening is the fourth case investigated by Hannover — two have been shelved because the suspects have been deemed unfit for trial, and one was closed when the suspect died.

Holtermann said, however, his client is in good health.

Thomas Walther, who represents 20 Auschwitz victims and their families as co-plaintiffs in the case against Groening as allowed under German law, said it's their last chance "to participate in bringing justice to one of the SS men who had a part in the murder of their closest relatives."

"Many of the co-plaintiffs are among the last survivors of Auschwitz," he told the Associated Press.

Former Nazi guards' roles in individual murders have been notoriously hard to prove. German federal prosecutors have been emboldened, however, by the 2011 conviction of John Demjanjuk on 28,060 counts of accessory to murder. Demjanjuk, who was sentenced to five years in prison, died while appealing the conviction at age 91.

Additional reporting by Mashable