Global Policy Forum

By Douglas Jehl

The new chief weapons inspector in Iraq told Congress on Tuesday that a lack of cooperation from ousted Iraqi officials was thwarting American efforts to untangle the many remaining mysteries surrounding Iraq's suspected illicit weapons program.

In the public version of testimony delivered behind closed doors to two Senate committees on Tuesday, the inspector, Charles A. Duelfer, acknowledged that American inspectors had still not found any evidence of an illicit arsenal. But he seemed less inclined than his predecessor, David Kay, to close the door on the possibility that such weapons might yet be found, saying that inspectors were continuing to pursue leads — "some quite intriguing and credible" — about concealed caches.

A top Democratic senator, Carl Levin of Michigan, later complained that the public version of Mr. Duelfer's testimony had omitted information contained in the classified version that would have raised further doubts about whether Iraq possessed illicit weapons at all.

Through a spokesman, Mr. Duelfer responded by saying that the two versions of his testimony "mirror each other, consistent with the protection of sources, methods and other classified intelligence information."

Senator Levin, who serves on both panels that Mr. Duelfer addressed in closed session, asked the Central Intelligence Agency to declassify the entire report, to the fullest extent possible, "so the public can reach their own conclusions."

Mr. Duelfer, who took charge of the search in January, said at a news conference on Capitol Hill that the picture of Iraq's suspicious activities "is much more complicated than I anticipated going in." He said he could not predict how much more time he might need before he reached final conclusions about what illicit weapons, if any, Iraq possessed at the time of the American invasion last March.

"The people we need to speak to have spent their entire professional lives being trained not to speak" about illicit weapons, Mr. Duelfer said in a public version of his testimony. He said that Iraqi scientists and engineers were keeping silent both out of fear of prosecution or arrest by American officials, and out of fear of retribution from supporters of the former government of Saddam Hussein.

Mr. Duelfer took over from Mr. Kay, who at the time of his resignation in January said that American officials were "almost all wrong, probably" in assessing before the war that Mr. Hussein's government possessed illicit weapons. Mr. Duelfer said Monday that inspectors had uncovered new information that Iraq had in place before the war at least the technical ability to use civilian facilities to quickly produce the biological and chemical agents needed for weapons.

Still, Mr. Duelfer said: "We do not know whether Saddam was concealing W.M.D. in the final years or planning to resume production once more sanctions were lifted. We do not know what he ordered his senior ministers to undertake. We do not know how the disparate activities we have identified link together."

The status report issued by Mr. Duelfer was the first such update since October, and it came nearly 10 months after Mr. Kay and his Iraq Survey Group began their hunt last June. The failure of American inspectors to find illicit weapons in Iraq has prompted Democrats, including Senator John Kerry of Massachusetts, the party's presumptive presidential candidate, to press the Bush administration to acknowledge having been wrong in the prewar assessments in which senior officials described Iraq's weapons program as a principal reason for going to war.

In urging patience, however, Mr. Duelfer was echoing the calls made by President Bush and by George J. Tenet, the director of central intelligence, to whom he reports as a special adviser. Two Republican senators, Pat Roberts of Kansas, who heads the Senate Intelligence Committee, and John W. Warner of Virginia, who heads the Senate Armed Services Committee, both joined Monday in asking for more time before any final judgments are reached.

Mr. Duelfer expressed a particular frustration about what he described as "the extreme reluctance of Iraqi managers, scientists and engineers to speak freely."

Even a year after the American invasion, he said, "obtaining clear, truthful information from the senior Iraqi leadership has been problematic even at this point in time." While officials of the Iraq Survey Group had met with "hundreds of scientists," he said, it had yet to identify who in any particular program had played the most critical roles.

"Many people have yet to be found or questioned, and many of those we have found are not giving us complete answers," he said. And while American investigators had recovered millions of documents, he said, millions more were destroyed, while a shortage of people who can translate Arabic meant that only a "tiny fraction" of the whole had yet been fully translated. Among former Iraqi officials willing to talk, he said, "they oftentimes are the ones we know were not in the inner circle."