The CIA has launched an internal review of how it trains and deploys security officers overseas after a fatal shooting by one of the agency’s contractors in Pakistan triggered a diplomatic crisis and new recriminations between the two nations’ spy services, U.S. officials said.

As part of the probe, the agency is expected to examine decisions on where security guards are sent, the scope of their activities in foreign assignments, and the rules of engagement that govern how and when they may use lethal force, officials said.

Officials stressed that the review is not expected to scrutinize the conduct of Raymond A. Davis, a contractor who fatally shot two Pakistani men on Jan. 27 and returned to the United States this week after being released from a Pakistani jail in Lahore.

Even so, the decision to launch an internal review suggests that the Davis case has triggered broader concerns among senior CIA officials about its vast and largely contract-hired security staff.

The aim of the review is “not how does our guy get into a shoot-out,” said a senior U.S. intelligence official familiar with the probe. “It’s more how do you use security officers in the field. What’s their role? How many and where” are they used?

CIA Director Leon E. Panetta ordered the the review last month “with an eye toward strengthening the ability of agency security officers to protect operations and personnel,” said a second U.S. official.

Rep. Mike Rogers (R-Mich.), the chairman of the House Intelligence Committee, said he doesn’t fault Davis’s conduct, but expressed concern over “the mistrust that has built up over this incident” between the United States and Pakistan.

“This clearly has strained the relationship,” Rogers said.

The frictions intensified after a CIA drone strike Wednesday killed as many as 40 people that Pakistani authorities said included a large number of civilians. A U.S. official disputed the claim, saying, “This was a group of terrorists. We’re not talking about a bunch of guys who were playing pinochle at the local Kiwanis club.”

The Justice Department is investigating the Davis shooting, which occurred when he was engaged in what CIA officials refer to as “area familiarization” work in a busy section of Lahore. Davis, 36, said the two men he shot were armed and attempting to rob him at a traffic signal.

Davis “did exactly what he was supposed to do,” said the U.S. official, who added that Panetta addressed the agency’s security staff last week “to thank them and express support for all they do.”

But some CIA veterans said they are puzzled as to why Davis fired as many as nine rounds from his weapon, and may have lingered at the scene before being detained — outcomes that case officers are trained specifically to avoid.

The case has also raised new concerns about the agency’s use of contractors, a practice that came under severe criticism in connection with treatment of CIA detainees — including one who was beaten to death by a contractor in Afghanistan — after the Sept. 11 attacks.

Davis worked for the CIA’s Global Response Staff, a sprawling security wing that is “heavily” dependent on contractors to fill positions providing security to operatives overseas, said a former CIA official involved in overseeing the group’s work.