WASHINGTON — Secretary of State Hillary Clinton sent and received emails through her private server containing sensitive U.S. and foreign government information on a range of issues — from an American detained in Myanmar and Iran’s nuclear program to the Afghanistan war — that State Department reviewers have classified.

The correspondence, which dates to Clinton’s first months in office in 2009, raises fresh questions about her handling of sensitive national security material as she seeks the 2016 Democratic presidential nomination, providing new political ammunition for the Republican hopefuls she leads in the polls.

The State Department released the emails after they were scrubbed for classified information in response to a lawsuit filed by the Associated Press after it was disclosed she had used the private server located at her home in Chappaqua, New York, instead of her official State Department system.

The review found that a large number of the emails contained “foreign government information” or information pertaining to the “foreign relations or foreign activities of the United States, including confidential sources,” according to codes printed on the censored portions of the correspondence.

Even though the information clearly was sensitive, none of the emails was stamped secret or marked with any other level of classification. The vast majority were sent by experienced U.S. and foreign diplomats or other officials using secure official email systems and then forwarded to Clinton via her unsecured server by a small circle of close aides and advisers.

Several messages were sent from private email accounts. In one case, Clinton’s then-deputy chief of staff, Huma Abedin, forwarded a Nov. 21, 2009, message from then-British Foreign Secretary David Milliband with the subject line, “Another note from milliband that he doesn’t want to send through the system.”

The note, which was excised by State Department reviewers, concerned a visit to war-stricken Afghanistan from which Milliband had just returned.

State Department spokesman Mark Toner said that in total, portions of 37 documents, many of them duplicates, were classified during the review. There are 64 separate redactions in those 37 documents, he said.

“To date, we’ve not seen any classified information that should have been classified at the time,” he said. “We’ve upgraded some of this information, and that’s a very common practice, but we have not seen anything as we’ve conducted this review that indicates any information should have been classified at the time.”

The State Department has released nearly 12 percent of some 30,000 Clinton emails, though Toner admitted Friday’s release violated a court order requiring the department to release more than it has.

“What was released today seems to have some redacted portions that were classified during the review process,” Clinton campaign spokesman Nick Merrill said.

“None of these emails were marked classified at the time, so I’d refer you to the State Department on their processes.’”

Republicans pounced on the State Department’s review to level new charges of irresponsibility at Clinton, who has insisted that using her private server wasn’t improper and that she hadn’t sent or received classified information over it.

“Today’s email dump shows Hillary Clinton put even more sensitive government information at risk on her secret email server than previously known,” Republican National Committee Chairman Reince Priebus said. “Hillary Clinton’s reckless attempt to bypass public records laws put our national security at risk and shows she cannot be trusted in the White House. ”

Paul Pillar, a former top U.S. intelligence analyst and nonresident fellow at the Brookings Institution, a policy institute, said he didn’t understand why the secretary of state would use a personal, unsecured email system, calling it a risk to national security.

“She could have gotten whatever IT support was needed to make it convenient for her, and secure as well,” he said. That could have included providing Clinton with a secure BlackBerry, he added.

But Ivo Daalder, who served as U.S. ambassador to NATO under Clinton, said that in the age of mobile email, U.S. officials and military officers traveling overseas routinely send unclassified emails to their colleagues in the United States.

“The big story that people are missing is that today, with this administration and the previous administration, most of the communication that happens, happens when people are on the road, when they almost by definition need to resort to using unclassified systems, i.e. BlackBerries,” Daalder said.

Tom Blanton, executive director of the National Security Archive at The George Washington University, said that the State Department reviewers most likely were overzealous in censoring the emails, adding it wasn’t possible for Clinton to send classified documents or even segments of classified documents over her personal server.

Multiple email exchanges on numerous topics contained information that the State Department review determined should have been classified, according to a McClatchy review of the 1,356 emails released Friday.

— A series of emails dated Aug. 16, 2009, between Clinton and Jake Sullivan, who served as Clinton’s deputy chief of staff and now is her campaign’s top foreign policy adviser, related to the release by Myanmar of American John Yettaw, who was detained after visiting the home of opposition leader Aung San Suu Kyi.

Jim Webb, then a senator from Virginia and chairman of the Senate Foreign Relations subcommittee on East Asian and Pacific Affairs, secured Yettaw’s release during a two-day visit to Myanmar, once known as Burma. Webb is running for the Democratic presidential nomination against Clinton. His campaign did not respond to a request for comment Friday.

— An email from Clinton to the private email address of William Burns, then the No. 3 official at the State Department, contained information about Russian leaders and her upcoming trip to Central Asia. A sentence that begins with “As you know,” was excised. Most of his answer was redacted, although some sentences on Russia and Afghanistan were left in.

— In Nov. 25, 2009, Clinton responded to a note from Burns about an upcoming vote of the International Atomic Energy Agency on whether to censure Iran for secretly building a uranium enrichment plant. Most of Burns’ message and Clinton’s entire response an hour later were redacted on grounds the information related to foreign relations.

— An Aug. 15, 2009, email forwarded by Sullivan to Clinton about a trip to Pakistan by then-U.S. Special Envoy Richard Holbrooke was heavily redacted. “He proposes a simple message …” and the rest of the sentence was blanked out.

— Abedin forwarded to Clinton an email on Oct. 9, 2009, in which a top State Department official described “a long secure call” that morning with former Sen. George Mitchell, D-Maine, President Barack Obama’s special envoy to the Middle East. A portion of Assistant Secretary Jeffrey Feltman’s brief synopsis of the call was classified in the review.

Also classified was a portion of Feltman’s email describing an attempts to have Mitchell brief former Secretary of State Henry Kissinger an hour before Kissinger was to take a call from Israeli Prime Minister Benjamin Netanyahu. At 6:13 the next morning, Oct. 10, Abedin sent Clinton a now-censored account of Mitchell’s conversation with Omar Solimon, former Egyptian President Hosni Mubarak’s feared intelligence chief.

The latest batch of emails was the third released since May. The first collection related to the Sept. 11, 2012, attacks on U.S. compounds in Benghazi, Libya, in which four Americans, including the U.S. ambassador, were killed. The second release came in June.

The latest release came a day after McClatchy reported that an email released in June and four still held by the State Department contain classified information from five U.S. intelligence agencies and included material related to the Benghazi attacks.

Two inspectors general have indicated that the five emails were not marked classified at the time they were stored on her private server but that the contents were in fact “secret.”

Clinton has agreed to testify about her email arrangements on Oct. 22 before the House committee investigating Benghazi.

Writers Daniel Desrochers and Greg Gordon contributed to this report.

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