A mid-level intelligence officer assigned to the CIA persistently questioned the targeting of a building that turned out to be the Chinese Embassy in Yugoslavia, but his concerns went unheeded inside the spy agency and at the U.S. military's European Command, a senior U.S. intelligence official said yesterday.

"I'm not sure that's the right building," the senior official quoted the analyst as saying.

Although NATO war planners say they meant to strike the Yugoslav Federal Directorate of Supply and Procurement, American B-2 bombers instead destroyed the Chinese Embassy in Belgrade on May 7, killing three Chinese civilians, wounding more than 20 others and causing strains in U.S.-Chinese relations that still have not been repaired.

Undersecretary of State Thomas Pickering traveled to Beijing last week and gave the Chinese government a formal, detailed explanation of how the building was mistakenly targeted. But Chinese officials, who have suggested that the United States deliberately bombed the embassy, called aspects of Pickering's explanation "not logical" and the failure to detect errors "inconceivable."

The analyst's warnings are noted in a classified internal report by the CIA's inspector general, which has not been made public but has been given to some members of Congress.

According to the senior intelligence official, the analyst had "some familiarity" with the Directorate of Supply and Procurement -- an arms purchasing agency -- and was not sure that his colleagues had correctly located it on a map.

"He was concerned, raised some questions, and they didn't get resolved," the senior official said. Another intelligence officer said the analyst "raised his doubts with working level counterparts" at both the CIA and the European Command in Stuttgart, Germany, but the questions "were never raised to senior levels before the strike took place."

The officials noted that the CIA is not usually involved in selecting targets during a military campaign. But because of a constant demand for new targets during NATO's 11-week bombardment of Yugoslavia, they said, the agency received a special request for assistance. Once the CIA had developed its list of targets, the officials said, that "target set" was vetted by the intelligence arm of the Joint Chiefs of Staff at the Pentagon and by the European Command, which managed the U.S. role in NATO's airstrikes.

According to a high-ranking State Department official, an intelligence officer got the correct address of the Yugoslav arms procurement agency from the Internet but then used the numbering of buildings on parallel streets to mistakenly identify a spot on a map of Belgrade. He took that map to an expert in aerial photography who determined coordinates for the building. The bombs accurately hit those coordinates, which turned out to be the Chinese Embassy. A cross-check of various databases listing sensitive sites, such as schools, hospitals and embassies, failed to catch the error because the data had not been updated after the Chinese Embassy moved in 1996.

David C. Leavy, spokesman for the National Security Council, declined to comment on the CIA inspector general's report, referring questions to the agency.

Pickering spent yesterday briefing leading members of Congress on his trip to Beijing. But the chairmen of both the House and Senate intelligence committees are far from satisfied with what they have been told by government investigators, and they have decided to seek a further probe by the Defense Department's inspector general, according to congressional sources.

Sen. Richard C. Shelby (R-Ala.) and Rep. Porter J. Goss (R-Fla.) want a separate Pentagon probe, sources said, because the CIA inspector general left so many military-related questions unanswered.

Goss, responding to China's demand that the United States "severely punish the perpetrators," said that disciplinary action is "exclusively our business, if any is warranted at all."

Clinton administration officials have promised to inform the Chinese government of the results of the investigations. "There will be some outcome as far as accountability," said one official. "There will be no sweeping under the rug."

At CIA headquarters, meanwhile, analysts and case officers involved in erroneously targeting the Chinese Embassy expressed concern that their actions could be unfairly judged and their careers jeopardized if policymakers hunt for scapegoats.

At least one veteran CIA case officer with a military background has retained a lawyer. "We are concerned because there is a great deal of political pressure to blame someone, to blame an individual," said attorney Roy W. Krieger, who declined to identify his client but said he was "involved in the chain of command in the accidental targeting of the Chinese Embassy."

Krieger took strong exception to statements issued by the Chinese government last week summarizing Pickering's explanation of the embassy bombing. Among other things, the Chinese quoted Pickering as saying that a U.S. intelligence officer used techniques that are "totally inappropriate for precision targeting for air attacks."

A senior State Department official confirmed the accuracy of that part of the Chinese account.

Krieger responded that his client had acted appropriately in the absence of "operational rules" for targeting and had followed a standard U.S. military procedure for pinpointing targets on street maps. But Krieger, who has been granted a security clearance to represent CIA employees, said agency lawyers have prohibited him from publicly discussing the procedure.

"Clearly the means of identifying the building was inappropriate, flawed," one administration official said. "The system of checks and balances didn't work."