The American who fatally shot two men in Pakistan last month and who has been described publicly as a diplomat is a security contractor for the CIA who was part of a secret agency team operating out of a safe house in Lahore, U.S. officials said.

The contractor, Raymond Davis, 36, has been detained in a Pakistani jail since his arrest. He has said he opened fire on two Pakistani men after they attempted to rob him at a traffic signal in Lahore.

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Pakistani security officials take Raymond Allen Davis to a court in Lahore. Davis’ arrest last month for allegedly shooting two Pakistanis has caused a diplomatic crisis. 2011 Associated Press file

The disclosure compounds an already combustible standoff between the United States and Pakistan at a time of growing distrust between them and complicates U.S. efforts to win Davis’s release.

President Obama and other senior administration officials have repeatedly described Davis as a diplomat who was assigned to the U.S. consulate in Lahore and have said he is entitled to immunity from prosecution in Pakistan.

But in fact, Davis has spent much of the past two years working as part of a group of covert CIA operatives, whose mission appears to have centered on conducting surveillance of militant groups in large cities including Lahore.

At the time of his arrest, Davis was based at a house with five other CIA contractors as well as an agency employee, a U.S. official said, speaking on condition of anonymity because of the sensitivity of the matter.

The official said the impact of the disclosure that Davis is a CIA contractor “will be serious.

“I think it’s going to make it a hell of a lot harder to get him out,” the official said. “I think ISI knows what this guy is, but I think this is just going to inflame the Pakistanis.”

The ISI is the acronym for Pakistan’s spy service, the Inter-Services Intelligence directorate.

“Our security personnel around the world act in a support role providing security for American officials. They do not conduct foreign intelligence collection or covert operations. Any assertion to the contrary is flat wrong,” said George Little, a spokesman for the CIA, without commenting specifically on Davis.

The Washington Post learned of Davis’s CIA affiliation after his arrest but agreed not to publish the information at the request of senior U.S. intelligence officials, who cited concern for Davis’s safety if his true employment status were disclosed.

Those officials withdrew the request not to publish Monday after other news organizations identified Davis as a CIA employee, and after U.S. officials made a final attempt to prevail upon Pakistan’s government to release Davis or move him to a safer facility.

U.S. officials reiterated their concern for Davis on Monday, and provided new details on the conditions at the jail where he is being held. One U.S. official said Davis had been moved to a separate section of the facility where the guards’ guns had been taken away “for fear that one of them may kill him.”

The official added that the jail holds about 4,000 inmates and that three detainees have previously been killed by guards.

“The local police are allowing angry protesters very near the prison,” the official said. He added that jail authorities were using dogs to taste or smell the food given to Davis “to make sure it doesn’t contain poison.”

Even while shedding new light on the circumstances of Davis’s detention, U.S. officials continued to provide scant information about his assignment. A former member of the U.S. Army Special Forces, Davis was hired as a contract employee of the CIA’s Global Response Staff, a unit that is responsible for providing security for agency employees and facilities in other countries.

Current and former U.S. officials said Davis had previously been employed by the sprawling security firm once known as Blackwater. A spokeswoman for the company, now known as Xe Services, did not respond to a request for comment.

U.S. officials said that at the time of the shooting, Davis was doing what CIA employees refer to as “area familiarization,” meaning basic surveillance designed to familiarize operatives with their surroundings.

The work would help to explain a collection of items found in Davis’s possession when he was arrested, including a camera, a small telescope, a first-aid kit, flashlights, and a Glock semi-automatic pistol.

The description of his activities is at odds with early accounts by U.S. officials who had indicated that he was not on a particular assignment when the shooting occurred and that he was attacked in his vehicle after withdrawing money from an automated teller machine.

Davis has testified that he was approached by two Pakistani men on a motorcycle, and that they brandished a weapon in an apparent attempt to rob him.

Pakistani authorities have threatened to charge Davis with murder and have released pages from police reports indicating that he fired at the backs of the men he killed even as they attempted to flee.

Officials in Pakistan said the government has known that Davis worked for the CIA and that the U.S. acknowledgment bolsters Islamabad’s case that Davis was not a diplomat and therefore is not entitled to immunity.

Davis’s affiliation with the CIA was “one of the major reasons” for the complications surrounding the case, a senior Pakistani official said.

The broader impact, the official said, will be in “adding to the public anger and anguish, and hence more pressure on authorities in Islamabad not to succumb to the American pressure to hand over Davis.”

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