The Flynn plea agreement contains a "cooperation" section, one that did not appear in the agreement for George Papadopoulos.
Flynn resigned as Trump's national security adviser in February.
The president's son denies boasting about getting golf course funding from Russians.
Republican lawmaker says Mueller "must step down immediately" because of ties to the Obama administration.
An unidentified defendant in the investigation is set to be detained on Monday.
The district attorney received political donations from lawyers connected to cases he dropped.
But the Senate intelligence committee's probe is moving forward.
Hicks is one of six past and current Trump administration aides whom Robert Mueller reportedly wants to question.
The Senate and House intelligence committees and the Senate Judiciary Committee are overseeing investigations into Russian meddling in the presidential election.
Former Chief of Staff Reince Priebus is among those said to be of interest to the special counsel.
U.S. investigators are probing whether there was collusion between the Kremlin and Trump's Republican presidential campaign.
Michael Caputo, a former campaign communications adviser, is among those going out-of-pocket for legal costs.
The president sent out several tweets on Sunday.
Scaramucci said the president told him it wasn't certain Russia meddled in election.
Anthony Scaramucci said he wanted to deescalate things regarding Russia.
The president has wheeled out tweets about Clinton as news of his son's meeting with a Russian lawyer continues.
Trump, Vice President Pence, Attorney General Sessions and others have retained lawyers, some of whom are controversial.
Why is the House Russia probe interviewing Trump's digital campaign director?
Kislyak figures prominently in at least three strands of the Russiagate scandal—is he just doing his job or trying to subvert American democracy?
Subpoenas under threat of contempt are the only path Congress can take to get the answers it needs.