Flynn pleaded guilty Friday to lying to the FBI about contacts he had with the Russian ambassador. Trump said he fired Flynn because he lied to the vice president and the FBI about those dealings.
"It is a shame because his actions during the transition were lawful. There was nothing to hide!" Trump said in a tweet, his second comment of the day of the explosive turn of events in the Russia probe.
It is now moving closer to the Oval Office itself as Flynn has agreed to cooperate with special prosecutor Robert Mueller.
With this new tweet Trump seems to admit for the first time that he knew Flynn lied to the FBI, which is a crime.
Trump's ties with Flynn have been under intense scrutiny since FBI director James Comey was fired by the president in May.
Comey testified before a Senate panel in June that after Flynn's firing, Trump asked Comey to drop an investigation into the former national security director.
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