AFP PHOTO / FILES-/AFP/GettyImages Undated file photo shows the late al-Qaeda leader Osama bin Laden at an undisclosed location in Afghanistan.

The top U.S. special operations commander, Adm. William McRaven, ordered military files about the Navy SEAL raid on Osama bin Laden's hideout to be purged from Defense Department computers and sent to the CIA, where they could be more easily shielded from ever being made public.

The secret move, described briefly in a draft report by the Pentagon's inspector general, set off no alarms within the Obama administration even though it appears to have sidestepped federal rules and perhaps also the U.S. Freedom of Information Act.

An acknowledgement by Adm. William McRaven of his actions was quietly removed from the final version of an inspector general's report published weeks ago. A spokesman for the admiral declined to comment. The CIA, noting that the bin Laden mission was overseen by then-CIA Director Leon Panetta before he became defense secretary, said that the SEALs were effectively assigned to work temporarily for the CIA, which has presidential authority to conduct covert operations.

"Documents related to the raid were handled in a manner consistent with the fact that the operation was conducted under the direction of the CIA director," agency spokesman Preston Golson said in an emailed statement. "Records of a CIA operation such as the (bin Laden) raid, which were created during the conduct of the operation by persons acting under the authority of the CIA Director, are CIA records."

Golson said it is "absolutely false" that records were moved to the CIA to avoid the legal requirements of the Freedom of Information Act.

The records transfer was part of an effort by McRaven to protect the names of the personnel involved in the raid, according to the inspector general's draft report.

But secretly moving the records allowed the Pentagon to tell The Associated Press that it couldn't find any documents inside the Defense Department that AP had requested more than two years ago, and would represent a new strategy for the U.S. government to shield even its most sensitive activities from public scrutiny.

"Welcome to the shell game in place of open government," said Thomas Blanton, director of the National Security Archive, a private research institute at George Washington University. "Guess which shell the records are under. If you guess the right shell, we might show them to you. It's ridiculous."

McRaven's directive sent the only copies of the military's records about its daring raid to the CIA, which has special authority to prevent the release of "operational files" in ways that can't effectively be challenged in federal court. The Defense Department can prevent the release of its own military files, citing risks to national security, but that can be contested in court and a judge can compel it to turn over non-sensitive portions of records.

Transferring government records from one executive agency to another must be approved in writing by the National Archives and Records Administration, under the Code of Federal Regulations. There are limited circumstances when prior approval is not required, such as when the records are moved between two components of the same executive department. The CIA and Special Operations Command are not part of the same department.

The Archives was not aware of any request from the U.S. Special Operations Command to transfer its records to the CIA, spokeswoman Miriam Kleiman said. She said it was the Archives' understanding that the military records belonged to the CIA, so transferring them wouldn't have required permission under U.S. rules.

Other rules from the chairman of the Joint Chiefs of Staff dictate that records about military operations and planning are to be considered permanent and after 25 years, following a declassification review, transferred to the National Archives.

Also, the Federal Records Act would not permit agencies "to purge records just on a whim," said Dan Metcalfe, who oversaw the U.S. government's compliance with the Freedom of Information Act as former director of the Justice Department's Office of Information and Privacy. "I don't think there's an exception allowing an agency to say, 'Well, we didn't destroy it. We just deleted it here after transmitting it over there.' High-level officials ought to know better."

It was not immediately clear exactly which Defense Department records were purged and transferred, when it happened or under what authority, if any, they were sent to the CIA. No government agencies the AP contacted would discuss details of the transfer.

The AP asked for files about the mission in more than 20 separate requests, mostly submitted in May 2011 — several were sent a day after President Barack Obama announced that the world's most wanted terrorist had been killed in a firefight. Obama has pledged to make his administration the most transparent in U.S. history.

McRaven's unusual order would have remained secret had it not been mentioned in a single sentence on the final page in the inspector general's draft report that examined whether the Obama administration gave special access to Hollywood executives planning a film, "Zero Dark Thirty," about the raid. The draft report was obtained and posted online last month by the Project on Government Oversight, a nonprofit watchdog group in Washington.

McRaven described steps he took to protect the identities of the SEALs after the raid, directing that their names and photographs not be released.

"This effort included purging the combatant command's systems of all records related to the operation and providing these records to another government agency," according to the draft report. The sentence was dropped from the report's final version.

Current and former Defense Department officials knowledgeable about McRaven's directive and the inspector general's report told AP the description of the order in the draft report is accurate. The reference to "another government agency" was code for the CIA, they said. These individuals spoke on the condition of anonymity because they were not authorized to discuss the matter by name.

The Defense Department told the AP in March 2012 it could not locate any photographs or video taken during the raid or showing bin Laden's body. It also said it could not find any images of bin Laden's body on the USS Carl Vinson, the aircraft carrier from which he was buried at sea. The Pentagon also said it could not find any death certificate, autopsy report or results of DNA identification tests for bin Laden, or any pre-raid materials discussing how the government planned to dispose of bin Laden's body if he were killed. It said it searched files at the Pentagon, Special Operations Command headquarters in Tampa, Fla., and the Navy command in San Diego that controls the Carl Vinson.

The Pentagon also refused to confirm or deny the existence of helicopter maintenance logs and reports about the performance of military gear used in the raid. One of the stealth helicopters that carried the SEALs in Pakistan crashed during the mission and its wreckage was left behind.

Associated Press writer Kimberly Dozier contributed to this report.

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