Deputy attorney general Rod Rosenstein submitted a widely circulated memo to the president last month raising concerns over Mr Comey's performance, but Mr Trump later said he had already made the decision to fire Mr Comey. A day later, Rosenstein appointed Mueller as special counsel.
On Wednesday, the Washington Post reported that Mueller was investigating if Trump obstructed justice when he fired Comey. McCabe was referring to the agency's investigation into possible collusion between the Trump campaign and Russian officials. "Sad!" the president tweeted Friday. "Witch Hunt", President Trump tweeted on Friday morning.
Mr Trump is unlikely to face criminal prosecution as a sitting president, but obstruction of justice could be grounds for impeachment.
In a second tweet, Trump touted his "powerful" presence on social media, despite widespread criticism that his recurring rants on Twitter and other online media have only compounded his legal and political problems.
Brand was sworn in as associate attorney general on May 22. Last week, Comey testified in a Senate hearing that he believed he was sacked "because of the Russian Federation investigation".
Coli bacteria found in drinking water at US Open
It seems doubtful that Love IV can actually mount a challenge to win this weekend, but he could make the cut and make some noise. Rory McIlroy and Jason Day never recovered from theirs. "I was out of it. trying to stay out of the way of Rory".
In an unusual move, Mr Rosenstein issued a statement on Thursday urging caution about reports based on "unnamed sources".
The Washington Post first reported that Robert Mueller wanted to question Dan Coats, the director of national intelligence; Adm. Michael S. Rogers, the head of the National Security Agency; and Richard Ledgett, the former deputy director of the NSA.
US Vice-President Mike Pence has hired a lawyer known for defending government officials in high-profile investigations to help him with probes into whether there were ties between the election campaign of President Donald Trump and Russian Federation.
Adding to the confusion is the fact that the special investigation is now being led by another former FBI director. While President Trump denied all the allegations levied on him, Comey revealed that the documented memos were a testament to his claims, a portion of which was published by the The New York Times, with the hope of a new counsel being appointed.