WASHINGTON -- The Army's top general says his service failed in a “significant” number of cases to report soldiers' criminal history to the FBI.

Gen. Mark Milley told reporters that the Army is still reviewing the extent of the problem. Last week the Air Force acknowledged that it had not submitted to the FBI, as was required, the 2012 assault conviction of the former airman who killed 26 people in a Texas church on Nov. 5.

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Milley said the Army is acting to quickly fix its reporting problem. He estimated that 10 percent to 20 percent of Army criminal history data that should have been reported to the FBI was not.

He added that this was an early estimate and he would provide a more specific number soon.