Kevin Johnson

USA TODAY

WASHINGTON -- The investigation into the operation of a private email server maintained by former secretary of State Hillary Clinton is nearing completion and investigators have interviewed a top aide to the Democratic presidential front-runner, a U.S. official said Thursday.

Longtime Clinton aide Huma Abedin has been interviewed, said the official who is not authorized to comment publicly.

The development was first reported by CNN on Thursday. Abedin’s attorneys could not be immediately reached for comment.

It is expected that within weeks investigators would move to interview Clinton about her handling of sensitive government information while she served as the nation’s top diplomat.

The official was not aware of any conclusions that investigators have reached in the ongoing inquiry.

Clinton’s use of a private email server while a member of the Obama administration and the inquiry into the security of classified information has shadowed her campaign throughout the primary season.

Earlier this week in an interview with MSNBC, Clinton said she had not yet been contacted by federal authorities to set up an interview.

In recent public statements, FBI Director James Comey has said that the investigation was continuing and that the only emphasis was to conduct a thorough review.

Abedin testified to the Benghazi Committee in 2015: