Several American intelligence agencies continue to investigate whether retired Gen. Michael Flynn's contact with at least one Russian official is in violation of federal law.

Jennifer Griffin reported last Fall that an interagency task force comprised of officials from the FBI, CIA, National Security Administration and the Treasury Department has been looking into Flynn's communications.

The government's probe is focusing on at least three members of Trump's campaign, including Flynn, who became National Security Adviser upon the president's inauguration.

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White House Press Secretary Sean Spicer said Monday that Flynn has indeed been in contact with the Kremlin's ambassador to the United States, Sergey Kislyak, but that Trump's team has not been informed of any specific investigations.

Spicer said Flynn and Kislyak conversed twice in December, discussing a Russian plane crash that killed a choir, a planned post-inauguration phone call between Trump and Putin and cordial Christmas greetings.

Trump and his team will not interfere with the investigation, Spicer said.

The FBI requested four Foreign Intelligence Surveillance Act (FISA) warrants in connection with their overall investigation, Griffin reported, adding that it was unclear if Flynn himself was the subject of any of those warrants.

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