Hundreds of naturalized U.S. citizens should not have been made Americans, a new federal report finds.

FOX's Jared Halpern has more from Washington:

At least 858 immigrants from countries of national security concern or with high rates of immigration fraud, were mistakenly granted citizenship, according to a Department of Homeland Security review.

The department's inspector general found the immigrants used different names or birthdates to apply for citizenship, but those discrepancies weren't caught because of fingerprints missing from government databases.

A fingerprint records gap was created because older paper records were never added to digital fingerprint databases in the 1990's.

In a statement, DHS says an initial review finds in some of these cases, the immigrants ultimately may have qualified for citizenship.

In Washington, Jared Halpern, FOX News.

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