The FBI reportedly cancelled its 2013 investigation into Orlando terrorist Omar Mateen after only 10 months because they viewed the terroristic threats he made as a reaction to “being marginalized because of his Muslim faith,” by his coworkers.

According to Fox News’ Catherine Herridge, the revelation came during a closed door meeting with FBI Director James Comey Monday afternoon.

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“Director Comey confirmed to reporters this morning that there was a full FBI investigation of Omar Mateen in 2013,” she explained. “It was 10 months in length, and it was opened after he told his coworkers that he had family connections to Al Qaeda, that he was a member of a Shi’a terrorism organization and that he hoped law enforcement would raid his home and assault his wife so that he could then retaliate and martyr himself.” (VIDEO: FBI Director — ‘I Don’t Think’ We Could Have Stopped Orlando)

“That investigation was very extensive,” Herridge continued. “It involved the use of confidential informants — also surveillance — by the FBI as well as two in person interviews with Mateen.”

[dcquiz] Herridge noted that during the 10 month investigation, “he was on a watch list, and if he attempted to buy a firearm during that period the FBI would have been flagged to that purchase.”

Finally, Herridge explained the reasons why the FBI called off the probe.

“At the end of 10 months the investigation was closed with no further action. They took Mateen’s statements he was trying to taunt his coworkers because he thought he was being marginalized because of his Muslim faith.”

The FBI’s decision to call off its investigation into Mateen follows a narrative detailed by counterterrorism expert Patrick Poole. (RELATED: Did FBI Training Material Purge Cause Agency To Drop The Ball On Orlando Shooter?)

Back in May, Poole described a “political warfare campaign” in which “analysts and subject matter experts were blacklisted, and books and training materials were purged from official counter-terrorism training programs government-wide.”

He wrote that this purge “contributed to clues being missed by the FBI in major terrorism cases, including last year’s bombing of the Boston Marathon.”

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