The FBI informed Congress on Friday it is investigating whether there is classified information in new emails that have emerged in its probe of Hillary Clinton's private server. The FBI said in July its investigation was finished.
The disclosure, in a letter from FBI Director James Comey, came just 11 days before the presidential election and thrust a political liability back into the headlines that Clinton's campaign thought had been resolved and begun to recede from the minds of voters. The FBI couldn't guarantee its investigation would be finished before Election Day.
Comey said the new emails prompted investigators to take another look at whether classified information had been mishandled, which had been the focus of its criminal investigation into Clinton's use of a private email server.
"In connection with an unrelated case, the FBI has learned of the existence of emails that appear to be pertinent to the investigation," Comey wrote. "I agreed that the FBI should take appropriate investigative steps designed to allow investigators to review these emails to determine whether they contain classified information, as well as to assess their importance to our investigation."
Comey stressed in his letter that the FBI could not yet assess "whether or not this material may be significant," or how long it might take to run down the new investigative leads.
A U.S. official told The Associated Press on Friday that the newly discovered emails emerged very recently and did not come from Clinton's private server. The official spoke on condition of anonymity because this person was not authorized to discuss details publicly.
It was unclear what the emails contained, who sent them, or what connection they might have to the yearlong investigation the FBI closed in July without recommending criminal charges. The FBI probe focused on whether Clinton sent or received classified information using a server in the basement of her New York home, which was not authorized to handle such messages.
Comey said in July that his agents didn't find evidence to support a criminal prosecution or direct evidence that Clinton's private server was hacked.
Clinton's campaign did not respond to request for comment.
Asked about Comey's letter during a campaign stop in Florida, Democratic vice presidential nominee Tim Kaine said he's "got to read a little more" before responding.
Comey, who has talked often about the FBI's need to be accountable to the public, promised extraordinary transparency about the investigation and during intervening months has authorized the release of investigative files from the case, which are normally kept confidential.
That stance also left Comey, a career federal prosecutor who has served under both Republican and Democratic administrations, open to criticism from leaders in both parties that he was trying to influence the outcome of the presidential race.
Clinton campaign surrogates were already suggesting Friday that the FBI director was putting a thumb on the scale. Had he waited until after Nov. 8 to announce the discovery of the new emails, however, Comey would surely have faced criticism for sitting on major news until after the new president had been selected.
The FBI's letter did not say which unrelated case had yielded the new lead. One possibility was the investigation by law enforcement agencies in New York and North Carolina examining online communications between former congressman Anthony Weiner, the estranged husband of Clinton aide Huma Abedin, and a 15-year-old girl.
The U.S. official who spoke to the AP said the new emails were unrelated to the ongoing FBI investigation into hacking of key players in the presidential election, which U.S. officials have formally blamed on the Russian government.
State Department spokesman Mark Toner said the department learned about the FBI letter from news reports and did not get any notification from the FBI. Toner pledged the department would "cooperate to the full extent that we can."
The White House, through a spokesman, also declined to immediately comment.
Republican immediately pounced on the news, hoping to shake up a presidential race where most polls appear to show Republican nominee Donald Trump lagging well behind Clinton.
House Speaker Paul Ryan said Clinton has "nobody but herself to blame."
"She was entrusted with some of our nation's most important secrets, and she betrayed that trust by carelessly mishandling highly classified information," Ryan, R-Wis., said in a statement. "This decision, long overdue, is the result of her reckless use of a private email server, and her refusal to be forthcoming with federal investigators. I renew my call for the Director of National Intelligence to suspend all classified briefings for Secretary Clinton until this matter is fully resolved."
Rep. Bob Goodlatte, R-Va., the chairman of the House Judiciary Committee, said the FBI's decision reinforces the committee's view that the more that is learned about the server, "the clearer it becomes that she and her associates committed wrongdoing and jeopardized national security."
Speaking to cheering supporters at a rally in New Hampshire, Trump used Comey's new letter to attack Clinton.
"We must not let her take her criminal scheme into the Oval Office," said Trump, who has pledged to "lock up" his political rival if elected. "Perhaps finally justice will be done."