WASHINGTON — The Department of Homeland Security granted citizenship to hundreds of people who had previously been ordered deported or removed under different names because of flaws in keeping fingerprint records, according to a report released Monday.

The report from the department’s Office of Inspector General found that nearly 900 individuals were granted citizenship because neither the agency nor the F.B.I. databases contained all of the fingerprint records of people who had previously been ordered to be deported.

Nearly 150,000 older fingerprint records were not digitized or simply were not included in the Department of Homeland Security’s databases when they were being developed, the report said. In other cases, fingerprints that were taken by immigration officials during the deportation process were not forwarded to the F.B.I.

“This situation created opportunities for individuals to gain rights and privileges of U.S. citizenship through fraud,” said John Roth, the inspector general at Homeland Security.