Specifically, someone within the intelligence community was concerned by a phone call Trump had with a foreign leader, which was said to include a "promise" that was so deeply troubling to that official that the person decided to lodge a formal whistleblower complaint with the inspector general.
A person directly involved with the discussions told the outlet the U.S. was concerned that Trump and his administration routinely mishandled classified intelligence and that their actions could expose the covert source as a spy within the Russian government.
John Kelly, President Donald Trump's new chief of staff, has garnered a reputation for running a tighter ship in a typically freewheeling White House since his arrival, and that reportedly extends to Trump's daughter and closest confidant, Ivanka Trump.
Violent clashes between white nationalists and counter-protesters in Charlottesville, Virginia took a deadly turn on Saturday when a driver plowed his vehicle through the crowd, killing a 32-year-old woman and injuring several others.
President Donald Trump's national security adviser, H.R. McMaster, addressed heightening tensions between the US and Russia, as well as Trump's understanding of the threat Russia poses, during an interview with MSNBC's Hugh Hewitt that aired on Sunday.
Senior officials at the FBI, the CIA, the Office of the Director of National Intelligence, and the Department of Justice knew as early as January that former national security adviser Michael Flynn could have been vulnerable to Russian blackmail, The New York Times reported on Tuesday.