White House national security adviser resigns

Michael Flynn, the White House's national security adviser, resigned Monday night.

The resignation came just after reports that the Justice Department warned the Trump administration last month that Flynn misled administration officials regarding his communications with the Russian ambassador to the United States. He potentially was vulnerable to blackmail by the Russians, according to CNN.

"I inadvertently briefed the vice president-elect and others with incomplete information regarding my phone calls with the Russian ambassador. I have sincerely apologized to the president and the vice president, and they have accepted my apology," Flynn wrote in his resignation letter.

With less than a month into the job, Flynn is one of the shortest-serving senior presidential advisers in modern history. Gen. Keith Kellogg will step into the role on an interim basis, sources told CNN.

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