The electronic device shared by Hillary Clinton aide Huma Abedin and husband Anthony Weiner on which the FBI found more Clinton emails was a laptop and it contained tens-of-thousands of emails, a senior law enforcement official told Fox News on Saturday.

The FBI announced Friday that it had restarted an investigation into emails Clinton sent on a private server system while secretary of state, as a result of a probe into Abedin’s husband, disgraced New York Democratic Rep. Anthony Weiner, “sexting,” or sending sexually-suggestive electronic messages, to a teenage girl.

The law enforcement official told Fox News that the laptop had “five digits” of emails, meaning tens-of-thousands of them. However, federal investigators remain unclear whether Abedin or Weiner own the laptop.

The FBI conducted a roughly two-year investigation into Clinton’s use of a private server system, finding several emails marked as classified and concluding that she had been “extremely careless.” However, the agency did not find evidence that Clinton had been criminally negligent and did not recommend criminal charges to the Justice Department.

People familiar with the case say the FBI started looking at the new cache of emails because the agency thought they were “pertinent to the investigation.”

The source also told Fox News that law enforcement officials think it’s highly unlikely that all of the new-found emails are duplicates, as the Clinton campaign has suggested.

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Fox News producer Jake Gibson contributed to this story.