A U.S federal judge has ruled that John Demjanjuk can be deported because he served as a guard at Nazi death camps during World War II.

Another federal judge had revoked the Ukrainian immigrant's American citizenship three years ago because of his wartime activities.

In 1981, U.S. courts stripped Mr. Demjanjuk of his citizenship. He was then deported to Israel, where a jury found him guilty of being the notorious camp guard 'Ivan the Terrible,' and sentenced him to death. Israel's Supreme Court overturned his conviction in 1998 after evidence showed he was the victim of mistaken identity. This forced U.S. authorities to reinstate his citizenship.

Mr. Demjanjuk has denied he was ever a guard at a Nazi death camp. He says he served in the Soviet army until being taken prisoner by the Germans in 1942.

He has until June 30 to appeal the judge's ruling.

Some information provided by AP and Reuters.