Hours after FBI agents executed a search warrant on his personal lawyer, President Donald Trump lashed out at the special investigation into Russian interference into the 2016 elections, denouncing a Monday raid as an "attack on our country."

"This is a pure and simple witch hunt," the President told reporters in the White House Cabinet Room. "It's a disgraceful situation."

"This is ridiculous, this is now getting ridiculous; they found no collusion whatsoever with Russia," Mr. Trump said. "There was no collusion at all, no collusion."

"I have this witch hunt, constantly going on, for over 12 months now," the President added, as he labeled the Russia investigators led by Special Counsel Robert Mueller as the "most biased group of people, these people have the biggest conflicts of interest I've ever seen."

Mr. Trump not only singled out Mueller for criticism, but also jabbed at Deputy Attorney General Rod Rosenstein, who hired Mueller to lead the investigation into Russian meddling in the 2016 election.

"Why don't I just fire Mueller?" Trump said when asked by a reporter. "Well, I think it's a disgrace what's going on - we'll see what happens."

"Many people have said you should fire him," the President added.

Flanked by top aides and senior military advisers, the President also raised the investigation of former Secretary of State Hillary Clinton over her personal email server, again making the case that she should have received much more scrutiny for that matter than what he has received over the 2016 election.

"There are crimes - and those crimes are obvious," the President said of the Clinton emails. "Lies, under oath, all over the place."

"33,000 emails were deleted after getting a subpoena from Congress. And nobody bothers looking at that," the President continued, again making it clear that he sees the Russia investigation as patently unfair.

"When I saw this, when I heard about it, that is a whole new level of unfairness," the President added.

The President's words about Mueller worried Democrats, who again warned Mr. Trump not to fire Mueller, a former FBI Director first appointed by President George W. Bush in 2001.

"The need for Congress to protect Mueller's investigation has never been more clear," said Sen. Cory Booker (D-NJ).

"President Trump’s continued attempts to obstruct this investigation must stop," said Sen. Bob Casey (D-PA).