FBI Director James Comey's announcement Friday that his agents had uncovered new emails related to their investigation of Hillary Clinton has scrambled the presidential race with little more than a week to go before Election Day.
Democrats have accused Comey of attempting to boost Donald Trump's chances by breaking with longstanding policies that bar law enforcement professionals from commenting on open cases. Republicans, in turn, have praised Comey for bucking the Justice Department's top brass, who reportedly advised against Comey's efforts to make the resurrected probe public.
While the FBI has not elaborated on what specifically triggered their interest in the new emails, here's what we know about the probe to date.
FBI agents have a search warrant
The bureau secured a search warrant for emails related to the Clinton probe on Sunday.
Agents discovered those emails on at least one device belonging to Anthony Weiner and Huma Abedin. Weiner, a disgraced former congressman, was under FBI investigation for a separate matter involving the sexually-charged messages and photographs he allegedly shared with a minor. Abedin, his now-estranged wife, was Clinton's deputy chief of staff at the State Department.
The warrant will allow investigators to search the emails on laptops shared by Abedin for records related to Clinton, the State Department or the Clinton Foundation, rather than information related only to Weiner's case.
Investigators discovered 650,000 emails
Agents must now sift through as many as 650,000 emails found on the devices used by Abedin and Weiner.
While Weiner may have produced some of those records, thousands could have come from the server Clinton set up in her basement during her State Department tenure. Abedin is the only other person known to have hosted an account on the "clintonemail.com" domain.
FBI never closed its Clinton Foundation probe
Investigators have continued their investigation into allegations of influence-peddling and financial misdeeds at the Clinton Foundation for more than a year. The bureau did not end that probe when Comey announced the end of the email-related investigation in July.
At least four FBI field offices are reportedly involved in gathering evidence for the investigation, despite the fact that Justice Department leaders discouraged the effort in February.
There are now four FBI investigations tied to Clinton
With the addition of the reopened Clinton email probe, the FBI is presently pursuing four separate investigations with ties to Clinton and her allies.
The first, and perhaps oldest, is the Clinton Foundation probe. The second is the investigation into Weiner's sexual misconduct, which last week dovetailed into a third probe of Clinton-related emails.
The fourth investigation involves the campaign finances of Virginia Gov. Terry McAuliffe. The longtime Clinton ally was accused of accepting illegal donations from a Chinese businessman.
Abedin has no idea how FBI found new emails
Abedin told her colleagues that she does not know how thousands of her emails ended up on a laptop belonging to her husband, Politico reported Monday.
She had previously turned over emails to the FBI from two laptops and a Blackberry phone.
Publicly, the Clinton campaign has maintained that they have no clue as to what the FBI might be investigating.
Democrats accused Comey of breaking the law
Sen. Harry Reid sent a scathing letter to Comey on Sunday that accused him, among other things, of violating the Hatch Act by announcing the investigation into newly-discovered emails on Abedin's computer.
The Hatch Act bars most executive branch officials from engaging in political activities.
Reid was among several Democrats who assumed Comey's move was an explicit effort to aid Trump's presidential campaign.
In an internal memo sent to FBI agents, Comey explained that he felt compelled to supplement his previous testimony before Congress with the new information given that his previous statements about the status of the investigation were no longer accurate.