Meanwhile, Massachusetts Democratic Sen. Edward Kennedy said Thursday that the case for going to war against Iraq was a fraud "made up in Texas" to give Republicans a political boost.
Smallpox fears were part of the case the Bush administration used to build support for invading Iraq — and they were raised again as recently as last weekend by Vice President Dick Cheney.
But a three-month search by "Team Pox" turned up only signs to the contrary: disabled equipment that had been rendered harmless by U.N. inspectors, Iraqi scientists deemed credible who gave no indication they had worked with smallpox and a laboratory thought to be back in use that was covered in cobwebs.
The negative smallpox findings reported to U.S. intelligence agencies come nearly six months after the administration went to war to disarm Iraq of weapons of mass destruction that Saddam long denied having and the military hasn't been able to find.
Smallpox was declared eradicated worldwide in 1980. All samples of the virus were to have been destroyed except those held by special labs in Atlanta and Russia, but some experts fear Russian samples could have gotten into the hands of hostile nations.
Two of the six members of Team Pox — whose existence and work hasn't been previously disclosed — have left Iraq while the rest remain involved in other aspects of the weapons hunt, said the officers who described the smallpox pursuit for the first time.
The smallpox team — which included two specialists who worked previously as U.N. inspectors in the 1990s — wrapped up their work midsummer mostly out of frustration with the Iraq Survey Group.
Those involved described missed opportunities caused by bureaucratic obstacles hampering the search effort. In several instances, the team couldn't follow up tips because of transportation problems.
Though Team Pox is no longer operational, having carried out their work between May and July, their findings don't dismiss the possibility that smallpox could still be discovered, according to the officials, who spoke on condition of anonymity. However, there remains little to pursue in this area now.
"We found no physical or new anecdotal evidence to suggest Iraq was producing smallpox or had stocks of it in its possession," one of the military officers said.
When Team Pox searched key locations in Iraq, such as the defunct Darwah foot-and-mouth disease center, they found the facility in the same condition U.N. inspectors left it in seven years ago.
In 1996, inspectors destroyed one fermenter, a storage tank and an inactivation tank at Darwah and poured concrete into the air conditioners while other equipment, including filter pressers and centrifuges were tagged for monitoring purposes.
The smallpox team found cobwebs covering much of the inside, although a CIA National Intelligence Estimate said the Iraqis were refurbishing the facility.
U.S. satellite images had spotted trucks pulling up in the past year — an indication of renewed activity, the team was told. But investigations on the ground revealed the trucks belonged to black marketeers stealing scrap metal and other parts around the site.
In the run-up to the war, the CIA said chances were even that smallpox was part of an Iraqi biological weapons program, according to the National Intelligence Estimate.
Bush administration officials often cited smallpox when describing Saddam's intentions — and continue to do so despite the lack of evidence.
On Sunday, Cheney said two trailers discovered in Iraq could have been used to make smallpox. The vice president referred to the trailers as "mobile biological facilities" — a characterization that has been disputed by intelligence analysts within two U.S. government agencies that believe the trailers were used to fill weather balloons.
Secretary of State Colin Powell, making the U.S. case for war last February at the United Nations, said Saddam "has the wherewithal to develop smallpox."
Some Iraqi scientists interviewed clearly had the know-how and expertise to produce smallpox, honed through years of work with similar viruses.
But none of the Iraqi scientists — many questioned at their offices at Iraqi universities — said they had done work on smallpox or other viruses that could be used in biological weapons programs.
U.N. inspectors suspected Iraq could have been working on smallpox or already had it. There was an outbreak of smallpox in the country in 1972, and Iraq admitted it had been producing the vaccine into the 1980s. And Iraq admitted to U.N. inspectors in the 1990s that its biological weapons scientists worked with camelpox, a close relative of the smallpox virus.
"From the onset the evidence was strictly circumstantial," said Jonathan Tucker, a former U.N. inspector and the author of a recent book on smallpox. "There was a lot of smoke but not much fire there."
In an interview with The Associated Press, Kennedy said the Bush administration has failed to account for nearly half of the $4 billion the war is costing each month. He said he believes much of the unaccounted-for money is being used to bribe foreign leaders to send in troops.
He called the Bush administration's current Iraq policy "adrift."
The White House declined to comment Thursday.
The Massachusetts Democrat also expressed doubts about how serious a threat Saddam Hussein posed to the United States in its battle against terrorism. He said administration officials relied on "distortion, misrepresentation, a selection of intelligence" to justify their case for war.
"There was no imminent threat. This was made up in Texas, announced in January to the Republican leadership that war was going to take place and was going to be good politically. This whole thing was a fraud," Kennedy said.
Kennedy was one of 23 senators who voted last October against authorizing President Bush to use military force to disarm Iraq.