WASHINGTON—A former staff member on the House Benghazi committee is suing the committee’s chairman for defamation, alleging he made false and reckless statements to the news media denigrating him.

In a suit filed Monday in federal court, former committee investigator Maj. Bradley Podliska alleges that Rep. Trey Gowdy (R., S.C.) and committee staff made “numerous false allegations to multiple national news outlets” after he announced his intention to sue the panel earlier this year over his termination from the committee.

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