Factbox – The four men charged in U.S. probe of Trump-Russia ties

(The Dec. 1 story was refiled to correct Gates’ first name to Richard in paragraph 3)

– Michael Flynn’s plea of guilty on Friday to lying to the Federal Bureau of Investigation made him the fourth person known to be charged in a U.S. Justice Department investigation of ties between President Donald Trump’s 2016 election campaign and Russia.

The other three known to be charged by Special Counsel Robert Mueller’s probe are: