Terror Expert: Don't Expect Calif. Attack to Be the Last on US Soil

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A former Homeland Security employee says he likely could have helped prevent the San Bernardino terror attack if the government had not pulled the plug on a surveillance program he was developing three years ago.

Philip Haney told Megyn Kelly tonight that as part of his investigation, he was looking into a collection of global networks that were infiltrating radical Islamists into the U.S.

But a year into the investigation, Haney said they got a visit from the State Department and the Homeland Security Office for Civil Rights and Civil Liberties, who said that tracking these groups was problematic because they were Islamic.

His investigation was shut down and 67 of his records were deleted, including one into an organization with ties to the mosque in Riverside, Calif., that San Bernardino terrorist Syed Farook attended.

Haney explained that if his work was allowed to continue, it could possibly have thwarted last week's attack.

"Either Syed would have been put on the no-fly list because association with that mosque, and/or the K-1 visa that his wife was given may have been denied because of his association with a known organization," Haney explained.

Trace Gallagher reported that DHS claims Haney's story contains "many holes," but declined to comment further due to privacy laws.

Watch more above.

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