Washington, Nov 7 (PTI): The FBI today gave a clean chit to Hillary Clinton, saying it has not changed its view after a renewed probe into her use of private email server as secretary of state, a development seen as a game changer for the Democratic presidential candidate.

"Based on our review, we have not changed our conclusions that we expressed in July with respect to Secretary Clinton," FBI Director James B Comey told Congress leaders in a letter.

The move, just before the general elections tomorrow, came as relief to the 69-year-old former secretary of state following the agency's announcement of launching a fresh probe into a cache of recently discovered emails that had triggered a backlash from the Democratic camp and dented Clinton's popularity.

Republican rival Donald Trump, who had seized on to the reignited controversy following the FBI's decision of the renewed probe, criticised the latest development, saying Clinton is being protected by a "rigged system" and that it is "unbelievable, what she gets away with".

A similar letter was sent to the Congress on July 28 in which Comey had said the FBI has reopened the investigation following discovery of some pertinent emails on the laptop of Clinton's close aide Huma Abedin which was shared by the latter's estranged husband Anthony Weiner.

"Since my letter (of October 28), the FBI investigation team has been working around the clock to process and review a large volume of emails from a device obtained in connection with an unrelated criminal investigation," Comey said. It was reported that there were 650,000 emails on that laptop.

"During that process, we reviewed all the communications that were to or from Hillary Clinton while she was the Secretary of State," Comey said. The FBI's letter was welcomed by the Clinton campaign, which saw its popularity graph sharply dropping down in the aftermath of the October 28 letter.

"We were always confident nothing would cause the July decision to be revisited. Now Director Comey has confirmed it," tweeted Clinton spokesman Brian Fallon. "We are glad to see that he has found, as we were confident that he would, that he had confirmed the conclusions he reached in July and we are glad that this matter is resolved," Jennifer Palmieri, Clinton's communications director, told reporters.

Clinton, who was campaigning in Cleveland, however, did not make any mention of it in her address. Trump challenged the FBI's statement, saying: "You can't review 650,000 emails in eight days."

"You can't do it folks. Hillary Clinton is guilty. She knows it. FBI knows it. Now, it is up to the people of the United States to deliver justice," the 70-year-old real estate tycoon told supporters in a Detroit suburb in Michigan.

In her address at Cleveland, Clinton said: "I want to really look at the faces of the people in front of me. I don't know your dreams, I don't know your struggles, but I want so much to convey to you that I will be on your side. I will never, ever quit on you."

Senator Dianne Feinstein in a statement said the FBI's letter should end the email saga once and for all. "The October surprise that came only 11 days before Election Day has unfairly hurt the campaign of one candidate and changed the tenor of this election.

Today's letter makes Director Comey's actions nine days ago even more troubling. There's no doubt that it created a false impression about the nature of the agency's inquiry," she said.

Democratic leader Nancy Pelosi said that after yet another exhaustive review of emails to and from Clinton, the FBI has again given her a clean bill of health. "While the original letter allowed days of innuendo and falsehood by Republicans desperate to divert attention from themselves, the FBI's swift and thorough review should finally close the door on this Republican sideshow.

"The American people will decide this election on the merits of the candidates - their values and their vision for America. Donald Trump is unfit to be Commander-and-Chief and unworthy of the office of President of the United States," she said.

Disagreed, said the Republican National Committee (RNC) chairman Reince Priebus. "The FBI's findings from its criminal investigation of Hillary Clinton's secret email server were a damning and unprecedented indictment of her judgment. The FBI found evidence Clinton broke the law, that she placed highly classified national security information at risk and repeatedly lied to the American people about her reckless conduct," he said.

"None of this changes the fact that the FBI continues to investigate the Clinton Foundation for corruption involving her tenure as secretary of state. Hillary Clinton should never be president," Priebus alleged.

Senate Minority leader Harry Reid said Comey created a political firestorm 11 days before a presidential election merely to confirm what people already knew: that Clinton's email practices were legal.

"Director Comey's actions were contrary to Justice Department rules and longstanding practice, and may have violated the Hatch Act. By confirming that the new emails were meaningless, today's letter underscores the irresponsibility of Director Comey's original letter," he said.