Who is Anthony Weiner?
New e-mails have been uncovered by the FBI which prompted officials to re-open investigations into Hillary Clinton's use of a private server - e-mails which came from a probe into former Congressman Anthony Weiner.
But who is he?
The basics:
52 years old, born in Brooklyn, New York
Member of the Democrat party
Served as a Congressman serving New York's 9th congressional district from January 1999 until June 2011
He resigned when the first of what turned out to be multiple sexting scandals was exposed
He ran, unsuccessfully, for New York City Mayor in both the 2005 and 2013 elections
The sexting scandals:
On May 27, 2011, Weiner posted a link to an explicit photograph of himself on his public Twitter account, addressed to an adult woman who was following him.
He spent several days denying he had posted the image, but finally admitted having "exchanged messages and photos of an explicit nature with about six women over the last three years".
Little over two years later, in July 2013, it emerged that he had sent explicit photographs to a 22-year-old woman under the alias "Carlos Danger".
Then, in August this year, the New York Post revealed he had once again been sending explicit photographs to another woman, including one showing him lying in bed next to his young son.
He and his wife, Huma Abedin, reportedly separated the next day.
Why was the FBI investigating him?
Allegations were made in September of this year that a 15-year-old girl had been among Weiner's sexting partners.
The Daily Mail carried an interview with the girl, along with sexually explicit pictures and graphic messages he is accused of sending to her during a "months-long" relationship.
The FBI, along with police in New York and North Carolina, launched an investigation into the claims - with the bureau's child sexual exploitation unit reportedly looking into the case.
How does this connect to Hillary Clinton?
Well, as yet, we don't really know.
A US official told The Associated Press that the newly-discovered e-mails which sparked renewed investigations into the Democrat presidential candidate came from the investigation into Weiner's online activities.
And the New York Times has reported that the messages were found on electronic devices seized from Weiner and Huma Abedin - who is the vice chairwoman of Hillary Clinton's campaign for president - as part of that case.
Exactly how it connects to the investigation into Mrs Clinton's use of a private e-mail server, an investigation which was officially concluded in July, is not yet clear.