Paul Morigi/Getty Images(WASHINGTON) — Former Secretary of State Hillary Clinton's security clearance was withdrawn by the State Department at her request, according to a letter from the agency to the Senate Judiciary Committee.

The letter, dated Sept. 21 and published Friday by the Republican chair of the committee, Sen. Chuck Grassley, does not detail why Clinton made the request, except that she did so on Aug. 30. An aide to Clinton did not respond to a request for comment.

The request came shortly after the Trump administration revoked former CIA Director John Brennan's security clearance, citing what White House press secretary Sarah Sanders said was "erratic behavior" and "a series of unfounded and outrageous allegations, wild outbursts on the Internet and television about this administration." To many, however, it was a naked attempt to punish a vocal critic. Brennan himself called it "part of a broader effort by Mr. Trump to suppress freedom of speech and punish critics."

At the time, the White House announced that it was also reviewing the security clearances of other former top officials, such as FBI Director James Comey, Director of National Intelligence James Clapper, National Security Advisor Susan Rice, National Security Agency Director Michael Hayden, and Deputy Attorney General Sally Yates.

But Clinton was not on the list.

The letter also says five other State Department officials, including Clinton's longtime aide Cheryl Mills, had their security clearances withdrawn, too. The names of the other four individuals are redacted, but all five had been designated as "researchers" by Clinton, allowing them to keep their clearance after they left the department.

Grassley had asked the State Department last year about the status of Clinton's security clearance and that of her top aides.

In 2016 while running for president against Trump, Clinton was investigated by the FBI and the State Department for her use of a private email server while secretary, but she was never charged with any crime, although then FBI Director Comey said he believed she had been "extremely careless."

The department's Bureau of Diplomatic Security will investigate whether any rules or laws were broken by Clinton's staffers after all their emails are reviewed to determine their classification status, according to the letter.

Grassley's office released the letter Friday night despite a warning from the State Department not to do so: "We request that you protect the information in this letter, as it is not public and generally not appropriate for public release… Should you wish to disclose any portions thereof, we ask that you provide the Department with a reasonable opportunity to inform the Committee of any sensitive information that should be safe-guarded," wrote acting Assistant Secretary of State for Legislative Affairs Charles Faulkner.

It's unclear whether Grassley's office did so.

The State Department would only confirm that Clinton made the request, referring further questions to Clinton.

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