The computer used by Hillary Clinton aide Huma Abedin and her now-estranged husband Anthony Weiner, which is now in the FBI's custody, may contain thousands of emails related to the bureau's earlier investigation of the Democratic nominee's private server.

Federal investigators are checking now to see if the emails on the shared laptop relate to official government work, or if they are classified, or if they are simply duplicates of emails authorities already processed, according the Washington Post.

The emails numbered "more than 1,000," including some that may be conversations between Clinton and Abedin, the Post noted.

The New York Times indicated separately that the number of emails was several thousand emails, adding that investigators are working now sort it all out.

"A senior law enforcement official said that tens of thousands of emails belonging to Ms. Abedin were backed up on Mr. Weiner's computer, which the F.B.I. had obtained as part of its investigation into Mr. Weiner," the Times wrote.

The Times report added, "Mr. Comey said in his letter to Congress that he did not know how long it would take to review the emails. Law enforcement officials said they did not know if and how many were duplicates of emails discovered in the earlier investigation."

The Post also stressed that it's too early to say whether the emails are significant, or whether some or all of them are duplicates of emails they've already seen.

Still, the news was enough to shake up the presidential campaign, which many said Clinton essentially had in the bag barring some unforeseen event.

Clinton was forced to address the matter at a press conference Friday evening, and Democrats were reportedly nervous about how the scandal might play in the press and among voters with less than two weeks to go before Election Day.

The emails were discovered as part of an investigation into Weiner, who was caught sexting a minor.

FBI Director James B. Comey informed Congress Friday that in the course of that investigation, his agency had found additional emails possibly related to the Democratic nominee's private 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.

He said additional "investigative steps" were needed to review the new trove of messages.

Clinton, her campaign chairman, her press secretary and the Democratic National Committee's interim chairwoman have each called on Comey to explain the meaning of his letter, and to produce whatever information he has involving the Democratic nominee.