Washington (CNN) Former FBI Director James Comey conceded that there was "real sloppiness" involved with the bureau's effort to obtain warrants to secretly surveil a Trump campaign adviser in 2016, saying in a Sunday interview that he was "overconfident" with his trust in the bureau's procedures.

"(The Justice Department's inspector general) also found things that we were never accused of, which is real sloppiness, and that's concerning. As I've said all along (it) has to be focused on. If I were director, I'd be very concerned about it and diving into it," Comey told "Fox News Sunday" host Chis Wallace.

Asked by Wallace about comments Comey made last year that he was sure officials at the FBI were "responsible" when they prepared surveillance warrants applications for Carter Page under the Foreign Intelligence Surveillance Act, the former FBI chief said he "was wrong."

"I was overconfident in the procedures that the FBI and (Department of) Justice have built over 20 year years. I thought they were robust enough," he said.

The comments from Comey come nearly a week after the department's inspector general released a report on the origins of the Russia investigation. The report found that the FBI properly opened its investigation into Russian election interference but said there were major errors in how the agency conducted the probe, including the critical finding that exculpatory evidence about Page was omitted from the applications for surveillance warrants.

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