The criminal probe into why former Bill Clinton aide Sandy Berger (search) illegally sneaked top-secret documents out of the National Archives (search) — possibly in his socks — has heated up and is now before a federal grand jury, The Post has learned.
[FOX News has confirmed the grand jury investigation.]
The "Socks Docs" probe forced Berger, who was President Clinton's national security adviser, to step down as Democrat John Kerry's top foreign-policy adviser last summer.
"It may have been off the front pages, but the investigation has been active," said a source with knowledge of the probe.
"[Berger] has been interviewed several times by federal agents — FBI and prosecutors."
Berger admits removing 40 to 50 top-secret documents from the archives, but claims it was an "honest mistake" made while he vetted documents for the 9/11 commission's probe into the Twin Towers attacks.
Berger has also acknowledged that he destroyed some documents — he says by accident.
It's unclear if he destroyed documents with handwritten notations that don't appear on other copies.
Some Republicans, such as House Speaker Dennis Hastert, have charged that Berger pilfered the documents because they were embarrassing to Clinton and Clinton aides such as Berger.
Asked if Berger has gotten a letter formally notifying him that he is the target of a criminal probe, a source close to him said, "He has not received any such letter."
So far, Berger hasn't testified under oath to the grand jury, the same source said.
The probe is being conducted by career prosecutors at the Justice Department, sources say.
The documents include multiple drafts of a review of the 2000 millennium threat said to conclude that only luck prevented a 2000 attack.
That story conflicts with Berger's own testimony to the commission, in which he claimed that "we thwarted" millennium attacks by being vigilant — rather than by sheer luck, as the review reportedly suggests.
The probe was touched off last spring when stunned archives staffers reported seeing Berger sneak classified documents out of a top-secret reading room in his pants and socks while vetting Clinton-era items for the commission.
They then ran a sting operation in which they coded some documents and confirmed they were missing when Berger left.
The documents were classified Code Word (search), the highest security classification, above Top Secret.
The commission report makes clear that Berger had a habit of writing candid notes in the margin of memos, sometimes flatly rejecting plans for action.
He nixed a plan to capture Usama bin Laden (search) with one word: "No."