The announcement by FBI Director James B. Comey that his agency was probing emails that might be related to Hillary Clinton's use of a private server while secretary of State sent shockwaves through the presidential campaign in its final days.
Word from Comey about the newfound correspondence rekindled a politically damaging controversy that has dogged Clinton since she launched her campaign last year.
Question: What did Comey say?
Answer: Not much. In a three-paragraph letter to members of Congress, Comey, who has served as FBI director since 2013, said newly discovered emails could be relevant to questions of whether Clinton and her aides mishandled classified information while she was secretary of State. He offered no details about the messages themselves and said he could not predict how long it would take for the FBI to determine whether they were relevant.
Q: So did the FBI reopen its investigation into Clinton's email use?
A: No. In July, the Justice Department declined to file charges in the case, based on Comey's recommendation. He concluded that although Clinton had been "extremely careless" in her use of a private email account while at the State Department, there was no "clear evidence that Secretary Clinton or her colleagues intended to violate laws governing the handling of classified information."
Q: What's Anthony Weiner's involvement?
A: The new emails Comey mentioned come from a computer jointly used by Clinton aide Huma Abedin and Weiner, her estranged husband, law enforcement officials said. The FBI came across the emails while investigating whether Weiner, a former New York congressman, violated federal law when exchanging sexually explicit texts with a teenage girl in North Carolina.
Q: How significant is this development?
A: It's unknown. Comey was vague, saying that the FBI "cannot yet assess whether or not this material may be significant." However, a federal official told the Los Angeles Times that the emails examined so far were not to or from Clinton, and contained information that appeared to be more of what agents had already uncovered.
Q: Then why did Comey announce it?
A: He told bureau employees in an email later Friday that he felt compelled to be transparent after announcing in July and testifying on Capitol Hill that the investigation was over. "I also think it would be misleading to the American people were we not to supplement the record," he wrote.
Q: What is Clinton's campaign saying?
A: The campaign is urging Comey to be even more transparent. Robby Mook, Clinton's campaign manager, said Comey "owes the public the full story, or he shouldn't have cracked open the door in the first place." Clinton herself has called Comey's letter "deeply troubling."
Democrats and Republicans alike are calling for additional information. GOP Indiana Gov. Mike Pence, Donald Trump's vice presidential running mate, tweeted that the FBI should "immediately release all emails pertinent to their investigation. Americans have the right to know before Election Day."
Q: How did Clinton get caught up in this email controversy?
A: While she was secretary of State, Clinton used a personal email address to conduct government business. The messages were stored on her family's personal server in the basement of her home in Chappaqua, N.Y. Clinton has said she used the account because she didn't want to carry two devices for personal and State Department communications. Other officials have said the State Department's official email system was cumbersome and difficult to use.
Clinton has since said that using a private server was a mistake and "not the best choice."