Trump was seemingly referring to the FBI's investigation into his campaign's and affiliates' potential collusion with Russian Federation ahead of the 2016 election. Comey was appointed in 2013 and had not yet served 6 years of what should have been a 10-year term.
"If we don't have an independent prosecutor, no-one is going to trust the result of an investigation undertaken by an FBI supervised by President Trump and his Justice Department", he said.
Though many Democrats have criticised Mr Comey's handling of the Clinton email probe, they said they were troubled by the timing of his dismissal. "I'm not shedding any tears for Comey personally - he hurt FBI's reputation - but I do worry whether we will ever get to the bottom of Russian Federation now", Brian Fallon, the campaign's erstwhile spokesman wrote on Twitter, adding.
"Given the recent controversies surrounding the director, I believe a fresh start will serve the Federal Bureau of Investigation and the nation well", said Republican Lindsay Graham of SC, chairman of a Senate Judiciary subcommittee investigating the Russian campaign interference.
White House adviser Kellyanne Conway on Tuesday denied that President Trump's decision to fire FBI Director James Comey was created to derail the bureau's investigation into Russian interference in the 2016 election. Hoover had been the only FBI director since the bureau was created in 1924.
When asked last week during a Senate hearing whether the president was part of the probe, Comey declined to answer.
"The Director was wrong", Rosenstein wrote, "to usurp the Attorney General's authority on July 5, 2016, and announce his conclusion that the case should be closed without prosecution".
Former campaign spokesman Brian Fallon said that while he believed Comey had "inflicted severe damage" on the FBI, "the timing and manner of this firing suggest that it is the product of Donald Trump feeling the heat on the ongoing Russian Federation investigation and not a well-thought-out response to the inappropriate handling of the Clinton investigation".
"President, with all due respect, you're making a big mistake, '" Schumer, a Democrat from NY and the minority leader of the Senate, said in a press conference on Capitol Hill. Clinton has called Comey's decision one of the reasons she lost the election.
Schumer spoke at a press conference shortly after word of Comey's firing became public.
Other current and former U.S. intelligence and law enforcement officials questioned the White House explanation for Comey's firing.
"This action only raises further questions regarding the administration's ties to Russia", Krishnamoorthi said. "If I can oppose his firing, so can you", he wrote on Twitter. "To me, that's the only logical explanation right now". Schmidt tweeted on Tuesday that senior administration officials told him the White House and the Justice Department had been working on firing Comey "since at least a week" ago.
He called on the deputy attorney general to appoint a special prosecutor for the investigation.