Washington CNN  — 

The chairman of the Senate Judiciary Committee released a scathing statement Friday, calling on Hillary Clinton to “come clean” after the State Department released an email in which she asked an aide to send information on a non-secure system after attempts to send the document securely failed.

Sen. Chuck Grassley said the email, released at about 1:30 am Friday morning along with about 3,000 other emails from Clinton’s State Department tenure, is “disturbing,” and “appears to show the former Secretary of State instructing a subordinate to remove the headings from a classified document and send it to her in an unsecure manner.”

On June 16, 2011, top Clinton aide Jake Sullivan wrote to Clinton to say she would get “tps” – presumably short for “talking points” that evening. The subject of the email is redacted so it’s not clear what topic these points covered.

The next morning, Clinton wrote back to say she hadn’t received them yet, and after a few minutes Sullivan responded that staff were having issues sending the document in a secure fax but that they were “working on it.”

“If they can’t,” Clinton replies, “turn into nonpaper w no identifying heading and send nonsecure.”

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Clinton’s critics are now seizing on the email, and say it shows a disregard of the security of classified information.

“It raises a host of serious questions and underscores the importance of the various inquiries into the transmittal of classified information through her non-government email server,” said Grassley, who went on to ask: “How long has the State Department been aware of this email? Why is it just now being released? Was her instruction actually carried out? If so, has the FBI opened a criminal inquiry into these circumstances?”

A State Department official declined to comment on Grassley’s statement, but told CNN earlier in the day that the department has “no indication at this time that the document being discussed was emailed to her.”

“I’m not going to speculate about whether the document being discussed was classified,” this official added. “Generally speaking, I can say that just because a document is sent via a secure method doesn’t mean that it’s classified. Many documents that are created or stored on a secure system are not classified.”

A spokesperson for Grassley’s office says it is working under the assumption the email was classified, since Clinton’s aides would have had other ways to send the document to her if it wasn’t, such as through email.

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Clinton’s email practices have been a source of criticism since March 2015, when it was revealed she used a private email server to conduct official business while at the State Department.

She has vehemently insisted she never sent or received information that was classified at the time it was sent.

The State Department has backed her on that claim, but have since retroactively classified information in over 1,000 of her emails.

The State Department is in the process of releasing Clinton’s work-related emails, which total nearly 55,000 pages, to the public, which is how this new email came to Grassley’s attention. The department is scheduled to release the last of Clinton’s emails at the end of this month.