The FBI is to scour 650,000 emails on the laptop of a former congressman connected to Hillary Clinton, it has been reported.
The Wall Street Journal tweeted: “Thousands may be tied to Clinton’s server.”
The Journal added that “metadata” on Anthony Weiner’s laptop had suggested such “ties”.
Its article reported that a review lasting “weeks” would examine the emails’ content, whether they were duplicates of messages already seen by the FBI, and whether they contained classified information.
Mr Weiner is the estranged husband of one of Hillary Clinton’s top aides, Huma Abedin.
A new investigation into Mrs Clinton’s emails came to light on Friday.
FBI director James Comey has said the probe will examine whether the messages contain sensitive government information.
Back in July, Mr Comey said that Mrs Clinton had been “extremely careless” in handling classified information while Secretary of State, and that scores of emails on her server contained highly classified information.