We believe that Iraq had lethal biological weapons agents, including anthrax, which it could quickly produce and weaponize for delivery by bombs, missiles, aerial sprayers and covert operatives. But we said we had no specific information on the types or quantities of weapons, agent or stockpiles at Baghdad's disposal.

What do we know today? Last fall the Iraqi Survey Group uncovered, quote, "significant information, including research and development of biological weapons, applicable organisms, the involvement of the Iraqi intelligence service in possible biological weapons activities and deliberate concealment activities."

All of this suggests that Iraq, after 1996, further compartmentalized its program and focused on maintaining smaller covert capabilities that could be activated quickly to surge the production of biological weapons agents.

The Iraq Survey Group found a network of laboratories and safe houses controlled by Iraqi intelligence and security services that contained equipment for chemical and biological research and a prison laboratory complex possibly used in human testing for biological weapons agents that were not declared to the United Nations.

It also appears that Iraq had the infrastructure and the talent to resume production, but we have yet to find that it actually did so, nor have we found weapons.

Until we get to the bottom of the role played by the Iraqi security services, which were operating covert labs, we will not know the full extent of the program.

Let me also talk about the trailers discovered in Iraq last summer.

We initially concluded that they resembled trailers described by a human source for mobile biological warfare agent production. There is no consensus within our intelligence community today over whether the trailers were for that use or if they were used for the production of hydrogen.

Everyone agrees that they are not ideally configured for either process but could be made to work in either mode.

To give you some idea of the contrasting evidence we wrestle with, some of the Iraqis involved in making the trailers were told that they were intended to produce hydrogen for artillery units. But an Iraqi artillery officer says they never used these types of systems and that the hydrogen for artillery units came in canisters from a fixed production facility.

We are trying to get to the bottom of this story.

And I must tell you that we are finding discrepancies in some claims made by human sources about mobile biological weapons production before the war. Because we lack direct access to the most important sources on this question, we have as yet been able to resolve the differences.