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The Justice Department announced Wednesday it has appointed former FBI Director Robert Mueller as a special counsel to oversee a federal investigation into the probe of alleged Russian influence in the 2016 presidential election.

The appointment came amid a growing Democratic outcry for someone outside the Justice Department to handle the politically charged investigation.

“In my capacity as acting Attorney General, I determined that it is in the public interest for me to exercise my authority and appoint a Special Counsel to assume responsibility for this matter," Deputy Attorney General Rod Rosenstein said in a statement. "My decision is not a finding that crimes have been committed or that any prosecution is warranted.”

The appointment gives Mueller, who led the FBI through the Sept. 11 terrorist attacks and served under presidential administrations of both parties, sweeping powers to investigate whether Trump campaign associates colluded with the Kremlin to influence the outcome in his behalf, as well as the authority to prosecute any crimes uncovered during the probe.

"I accept this responsibility and will discharge it to the best of my ability," Mueller said in a statement

The broad mandate, beyond any specific Trump-Russia connection, also covers "any matters that arose or may arise directly from the investigation."

Senior DOJ officials told Fox News the White House was informed of the decision for a special counsel after the order had been signed, through the White House Counsel’s office, about an hour before the decision went public.

"As I have stated many times, a thorough investigation will confirm what we already know – there was no collusion between my campaign and any foreign entity," President Trump said in a statement in reaction to the DOJ announcement. "I look forward to this matter concluding quickly.  In the meantime, I will never stop fighting for the people and the issues that matter most to the future of our country."

The Justice Department said Mueller has resigned from his job at a private law firm to take the job of special counsel.

The decision by the DOJ followed the revelation Tuesday that fired FBI Director James Comey wrote in a memo that President Trump had asked him to end an investigation into former national security adviser Michael Flynn.

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Rep. Jason Chaffetz, R-Utah, Chairman of the House Committee on Oversight and Government Reform, called the appointment a "great selection."

Sen. Jeff Merkley, D-Ore., praised the decision by the DOJ, calling it "a victory for all Americans."

“This is a victory for all Americans who believe in the integrity of the rule of law," he said. "This investigation must be given the full resources and independence it needs to succeed. We must follow the facts wherever they lead, and demand complete accountability for any wrongdoing that is found.”

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Mueller is the former FBI director  appointed by President George W. Bush who did a two year extension under President Obama beyond his 10-year fixed term before retiring in 2013.

He became FBI Director shortly before the  9/11 attacks, and was at the heart of turning the FBI into a counter terrorism and counter intelligence operation.

Muller, along with his then-deputy James Comey, threatened to quit over the Bush administration surveillance.

Muller's notes were used at the time to back up Comey's version of events, when they were questioned by the Bush White House.

Senate Intelligence Committee Chairman Richard Burr says the appointment of Mueller is a "good decision" that "assures the American people that there's no undue influence" in the probe of Russian meddling in last year's election.

Burr, who heads the Senate investigation into the Russian activity and possible connections to associates of President Donald Trump, says his committee will "continue to proceed forward" and the panel's job hasn't changed.

As special counsel, Mueller will have all the same powers as a U.S. attorney, though he will still ultimately report to Rosenstein. Still, he is not subject to the day-to-day supervision of the Justice Department. He can keep the same investigators in place, or request new or additional staff including from outside the department in addition to requesting a budget that includes personnel.

Some Republicans however expressed concern over the decision by the DOJ due to the wide scope of the influence that special prosecutors have.

"I'm worried with all special counsels because there's no control over them and they can abuse their power," Rep. Peter King of New York told the Associated Press.

In the 1990s, Democrats insisted that independent counsel Kenneth Starr, who investigated former President Bill Clinton, overstepped his authority.

Rosenstein appointed Mueller under a statute that has been used only once, in 1999, when John C. Danforth was appointed to investigate allegations of government wrongdoing in the siege at the Branch Davidian compound in Waco, Texas.

Danforth's investigation cost millions of dollars and included hundreds of interviews and a restaging of the final hours of the 51-day standoff with federal agents. He ultimately produced a 150-page report clearing then-Attorney General Janet Reno and other top government officials of any responsibility.

Fox News' Jake Gibson, Catherine Herridge and the Associated Press contributed to this report.