U.S. Army Sgt. Bowe Bergdahl at one point during his captivity converted to Islam, fraternized openly with his captors and declared himself a "mujahid," or warrior for Islam, according to secret documents prepared on the basis of a purported eyewitness account and obtained by Fox News.

The reports indicate that Bergdahl's relations with his Haqqani captors morphed over time, from periods of hostility, where he was treated very much like a hostage, to periods where, as one source told Fox News, "he became much more of an accepted fellow" than is popularly understood. He even reportedly was allowed to carry a gun at times.

The documents show that Bergdahl at one point escaped his captors for five days and was kept, upon his re-capture, in a metal cage, like an animal. In addition, the reports detail discussions of prisoner swaps and other attempts at a negotiated resolution to the case that appear to have commenced as early as the fall of 2009.

The reports are rich in on-the-ground detail -- including the names and locations of the Haqqani commanders who ran the 200-man rotation used to guard the Idaho native -- and present the most detailed view yet of what Bergdahl's life over the past five years has been like. These real-time dispatches were generated by the Eclipse Group, a shadowy private firm of former intelligence officers and operatives that has subcontracted with the Defense Department and prominent corporations to deliver granular intelligence on terrorist activities and other security-related topics, often from challenging environments in far-flung corners of the globe.

The group is run by Duane R. ("Dewey") Clarridge, a former senior operations officer for the Central Intelligence Agency in the 1980s best known for having been indicted for lying to Congress about his role in the tangled set of events that became known as the Iran-Contra scandal. He was pardoned by the first President Bush in December 1992 while on trial.

Clarridge counts a number of achievements in his spy career as well, including a prominent role in the establishment of a national counterrorism center at CIA, a move widely copied around the world by foreign intelligence agencies. A New York Times profile of Clarridge published in January 2011 disclosed the contractual relationship Eclipse had with the Pentagon, through subcontractors, and reported further that Clarridge's activities had included efforts to help find Bergdahl.

Clarridge told Fox News his group enjoyed a subcontract through the assistant Secretary of Defense for Special Operations and Low-Intensity Conflict from November 2009 through May 31, 2010, and that after the contract was terminated, he invested some $50,000 of his own money to maintain the elaborate network of informants and handlers that had yielded such detailed accounts of Bergdahl's status.

Clarridge further told Fox News that by the end of 2010, he had furnished at least 13 of these detailed SITREPs, or situation reports, that his network generated about Bergdahl to Brig. Gen. Robert P. Ashley Jr., who in April 2010 was named director of intelligence, at the J-2 level, at U.S. Central Command, or CENTCOM, headquartered at MacDill Air Force Base in Florida.

Clarridge said Eclipse SITREP # 3023, dated Aug. 23, 2012 -- in which a member of the Haqqani network, said to be close to Bergdahl's captors, reported that the American prisoner had declared himself a "mujahid" -- was among the reports provided to Ashley.

The latter is now commanding general at the U.S. Army Intelligence Center of Excellence and Fort Huachuca, where a message left with the public affairs office was not immediately returned.

The documents obtained by Fox News show that Eclipse developed and transmitted numerous status reports on the whereabouts of the errant American soldier, spanning a period from October 2009, roughly three months after Bergdahl reportedly walked off his base in Afghanistan and fell into custody of the Haqqani network, up through August 2012.

At one point -- in late June 2010, after Bergdahl succeeded in one of his escape attempts -- the Haqqani commanders constructed a special metal cage for him, and confined him to it. At other points, however, Bergdahl was reported to be happily playing soccer with the Haqqani fighters, taking part in AK-47 target practice and being permitted to carry a firearm of his own, laughing frequently and proclaiming "Salaam," the Arabic word for "peace."

Reached by telephone, retired U.S. Marine Corps Gen. James N. Mattis, a 45-year service veteran who served as CENTCOM commander from August 2010 to August 2012, told Fox News he may have received bits and pieces of the intelligence generated by Eclipse, but said Ashley, with whom he maintained a close working relationship, had not forwarded on to him the specific SITREPs cited by Fox News.

Mattis was also adamant that no one at CENTCOM or within the broader U.S. military or intelligence community -- despite intensive investigation of such allegations -- ever learned of anything to suggest Bergdahl had evolved into an active collaborator with the Haqqani network or the Taliban. "We were always looking for actionable intelligence," Mattis said. "It wasn't just the IC [intelligence community]. We had tactical units that were involved in the fight. We had SIGINT. Any collaborators who were on the other side and who came over to our side. We kept an eye on this. ... There was never any evidence of collaboration."

Fox News reported on Monday that Bergdahl was the subject of a "major classified file" prepared by the U.S. intelligence community, and that many members of that community harbored concerns that Bergdahl, during his period of captivity, may have engaged in collaboration with the enemy.

Experts consulted by Fox News said that SITREP # 3023 presents a picture of an American captive who, if not an active collaborator, may have succumbed to Stockholm Syndrome -- the dynamic by which hostages can become enamored of their captors and join their cause -- or simply feigned allegiance in order to survive. The report cited a source new to Eclipse -- a member of the Haqqani network said to be close to Mullah Sangeen, the Haqqani commander charged at all points over the last five years with operational custody and control of Bergdahl -- whose trustworthiness had not been fully vetted by the group. However, the report stated, the informant "does have plausible access to the information reported below, and claims to have seen Bergdahl personally in Shawal," in North Waziristan.

"In the early stages Sgt. Bowe Bergdahl's captivity," the report states, "he was held at Palasin, Naurak, FATA [Federally Administered Tribal Areas], under the control of Mullah Sangeen and under the direct supervision of Haji Mursaleem, Sangeen's father. Conditions and locality changed after Mursaleem died [in September 2010], and Bergdahl was kept under tight guard after his attempted escape from his new place of detention in Shawal.

"As of August 2012," the report continues, "the person with responsibility for Bergdahl's captivity is Sangeen's brother, who has delegated the actual guarding of Bergdahl to Abubakr Asadkhel, a Burra Khel Wazir loyal to Sangeen, and whose sub-tribe lives in Shawal. Abubakr leads approximately 200 armed men from his tribe and operates from five bases (markaz) in Shawal. ... Abubakr's tribe is one of the prosperous branches of the Wazir and owns lots of trucks. Abubakr circulates his prisoner between schools in the area he controls, and his different insurgent bases."

Conditions for Bergdahl have greatly relaxed since the time of the escape. Bergdahl has converted to Islam and now describes himself as a mujahid. Bergdahl enjoys a modicum of freedom, and engages in target practice with the local mujahedeen, firing AK47s. Bergdahl is even allowed to carry a loaded gun on occasion. Bergdahl plays soccer with his guards and bounds around the pitch like a mad man. He appears to be well and happy, and has a noticeable habit of laughing frequently and saying 'Salaam' repeatedly.

At other points, the SITREPs depict a much nastier relationship between Bergdahl and his captors. In July 2010, Eclipse SITREPs based on confidential talks with Afghan Taliban commanders reported that "the original command structure for the responsibility of holding the captured soldier remains intact."

Overall responsibility for the captive is in the hands of Haqqani commander Sangeen, with Bandiwan, one of his deputies, responsible for making the detailed arrangements. There are two locations where the soldier is kept: one in Degan and the other in Shawal, North Waziristan. When in Degan he is kept in the compound of Eid Wale, a local Dawr who is close to Sangeen and is a chromite dealer. The other location is at Shawal. The [source] confirmed that the soldier had been missing for five days and when he was recovered, he was a little worse from wear (lack of food; a bit slimmer) but otherwise in good health.

But an earlier dispatch stated that after his re-capture, on or about June 22, 2010, Bergdahl was "in ill-health, and has been collapsing."A SITREP dated one week before Bergdahl's ill-fated escape attempt placed him in the Bazaar area of Miramshah, and noted that "he seemed not to be tightly controlled."

The Eclipse reports suggest that negotiations over Bergdahl's fate began within a few months after his capture. An October 2009 SITREP disclosed that Sirajuddin Haqqani, the Pashtun warlord controlling the broader network that bears his name, had reached out through Pakistani political contacts to propose a prisoner swap. A July 2010 SITREP stated that two months prior, in late May, "negotiations between the Haqqani and representatives of the missing US soldier collapsed." At that point, the report said, Bergdahl was moved to a more secure location.

The New York Times, in its 2011 profile of Clarridge, described his agents' dispatches as "an amalgam of fact, rumor, analysis and uncorroborated reports." The fabled ex-spook made the more than one dozen SITREPs that Eclipse prepared on the Bergdahl case -- all previously unpublished -- available to Fox News because he wanted to demonstrate, as he put it: "We know what we're talking about."