Washington ? Weapons hunters in Iraq have found what they interpret as evidence of Iraqi preparations to secretly produce chemical and biological weapons, some Pentagon officials say.

But as the postwar weapons hunt enters its sixth month, it remains unclear whether they have found — or ever will — any evidence that Iraq had actually made such weapons or whether it simply was prepared to do so.

So far, the Bush administration has not announced anything that would validate the bulk of its prewar assertions about Iraq.

“What we have not yet shown, and what really counts, was that there were major, ongoing programs at the time we invaded Iraq,” said Anthony Cordesman, an Iraq expert at the Center for Strategic and International Studies in Washington.

The evidence of Iraqi preparations that the teams have found so far points to plans for weapons production that was to take place primarily at “dual-use” manufacturing facilities inside Iraq, the U.S. officials said. These are buildings with an overt, legitimate purpose, such as making pesticides or pharmaceuticals, but their equipment also can be used to make weapons.

No weapons have been reported found. The officials, who spoke on the condition of anonymity, did not know whether any evidence showed that Iraq had actually produced weapons or whether it simply had plans to do so.

Last week, David Kay, the CIA adviser heading up the search, told several members of Congress that he expected to find weapons of mass destruction, but that there also was the remote possibility he would not.

Defense Secretary Donald H. Rumsfeld, who met with Kay in Iraq on Saturday, said at a news conference in Baghdad that weapons hunters were “working diligently and professionally, and we all look forward to hearing what they have to say.”

Uncovered plans and interviews with Iraqis suggested certain sites were prepared to make weapons, the defense officials said. Many of the suspect facilities themselves were looted in the chaos after the war.

Searchers have found quantities of chemicals and substances that can be used to make both weapons and legitimate civilian items, the officials said. Castor beans, for example, can be used to make brake fluid for cars and the poison ricin.

Reaching indisputable conclusions about the intended purpose of these items and sites can be difficult. Unless something else proves a particular batch of castor beans was intended for ricin production, searchers will lack solid proof of a weapons effort.

CIA officials declined to comment on any discoveries. Officials say there is no timetable for Kay to report his findings.

“To date there has been no discovery that does not look like a residual or low-level effort growing out of what went on during the time before the Gulf War or when (pre-1998 U.N. inspectors) were still inspecting Iraq,” Cordesman said.