Federal authorities looking into the Anthony Weiner case first discovered the emails potentially related to the Hillary Clinton probe weeks ago, according to a law enforcement source familiar with the matter.
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The process that followed was a complicated one, with lots of back and forth over how to handle the situation and whether the FBI needed to get a warrant in order to review the newly discovered emails, according to the source.
The Clinton email investigators ultimately put together a summary of the situation and presented it all to FBI Director Comey last Thursday, after which he agreed that the Clinton email investigators should seek a warrant to review the newly discovered emails.
Federal authorities on Sunday obtained the warrant needed to start reviewing the emails found on a laptop used by Clinton aide Huma Abedin and her husband, Weiner.
Controversy has swirled around Weiner ever since it was first revealed in 2011 that the then-congressman posted a lewd photo to his Twitter account and later said he has engaged in "several inappropriate" electronic relationships with six women over three years. Weiner resigned from office 10 days later over the scandal.
He then ran an unsuccessful campaign for New York City mayor in 2013, which he lost amid another explicit photo scandal. These revelations were captured on camera by a documentary team that was filming his attempted comeback. Abedin announced that she was separating from her husband after yet another sexting scandal in August.
Abedin has been a longtime confidant and aide to Clinton and she has had a major role in the former secretary of state's run for the White House. The news of the additional emails came just 11 days before Election Day, sending shock waves through the campaign.
On Friday, Comey informed Republican and Democratic leaders in Congress that the bureau was again reviewing emails related to Clinton's personal server, after it learned of additional information that might be relevant to the case.
"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 in a letter released from the Hill last week.
This revelation set off a barrage of criticism with members of Congress and both presidential campaigns calling on the FBI to release additional information on the emails.
Friday's news comes nearly four months after Comey announced that no charges would be filed against Clinton over her use of a private emails server during her time as Secretary of State.
The revelation of new emails came as federal prosecutors were looking at whether Weiner sent an explicit text message to an underage girl in North Carolina. There is no evidence that Clinton or her team withheld information from the FBI during the original investigation and it is still unclear whether any of these emails have been sent from Clinton.