WASHINGTON, DC - JANUARY 22: Retired Lieutenant General Michael Flynn, U.S. national security advisor, arrives to a swearing in ceremony of White House senior staff in the East Room of the White House on January 22, 2017 in Washington, DC. Trump today mocked protesters who gathered for large demonstrations across the U.S. and the world on Saturday to signal discontent with his leadership, but later offered a more conciliatory tone, saying he recognized such marches as a "hallmark of our democracy." (Photo by Andrew Harrer-Pool/Getty Images)

US investigating Flynn calls with Russian diplomat

US investigators are scrutinizing calls between Mike Flynn, President Donald Trump's national security adviser, and Russia's ambassador to the US as part of a broader counterintelligence investigation of Russian activities in the US, law enforcement and intelligence officials tell CNN. Jim Sciutto reports.
A marching band rehearses on the East side of the US Capitol in Washington, DC during a dress rehearsal on January 15, 2017 five days ahead of the inauguration of US President-elect Donald Trump.

In inaugural disaster, an odd succession quirk

While security is in place and there is no specific, credible threat, a quirk in America's rules for succession raises questions about who would be in charge if an attack hit the incoming president, vice president and congressional leaders just as the transfer of power gets underway. CNN's Brian Todd reports.

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