The Justice Department is stripping U.S. citizenship from an Iowa man, who confessed to being a guard at two Nazi concentration camps in World War II.

A federal appeals court Tuesday upheld a lower court decision revoking 81-year-old John Hansl's citizenship.

Hansl was a guard at the Sachsenhausen concentration camp near Berlin and the Natzweiler camp in France.

The court ruled that Hansl had strict orders to shoot prisoners who tried to escape, marched them at gunpoint, and watched over them during slave labor.

The court said Hansl and other SS guards played an essential role in the Nazi genocide.

Hansl was born in present-day Croatia and came to the United States in 1955. It is unclear when and to which country he will be deported.

Some information for this report was provided by AFP.