Weapons hunters in Iraq are pursuing tips that point to the possible presence of anthrax (search) and Scud missiles (search) still hidden in the country, the chief searcher said Sunday.

David Kay (search) told Congress last week that his survey team had not found nuclear, biological or chemical weapons so far. But he argued against drawing conclusions, saying he expects to provide a full picture on Iraq's weapons programs in six months to nine months.

While lacking physical evidence for the presence anthrax or Scuds, Kay said tips from Iraqis are motivating the search for them.

Critics, including many in Congress, say Kay's findings do not support most of the Bush administration's prewar assertions that the United States faced an imminent, serious threat from Iraq's Saddam Hussein because of widespread and advanced Iraqi weapons programs.

President Bush has said the U.S.-led war on Iraq was justified despite the failure to find weapons.

Kay reported that searchers found a vial of live botulinum (search) bacteria that had been stored since 1993 in an Iraqi scientist's refrigerator. The bacteria make botulinum toxin, which can be used as a biological weapon, but Kay has offered no evidence that the bacteria had been used in a weapons program.

The live bacteria was among a collection of "reference strains" of biological organisms that could not be used to produce biological warfare agents.

Kay said Sunday the same scientist told investigators that he was asked to hide another much larger cache of strains, but "after a couple of days he turned them back because he said they were too dangerous. He has small children in the house."

Kay said the cache "contains anthrax and that's one reason we're actively interested in getting it." Kay, speaking on "Fox News Sunday," did not say whether the anthrax was live or a strain used only for anthrax research.

Before the war, Iraqis said they had destroyed their supply of anthrax. Inspectors haven't found any and Iraqis haven't been able to provide evidence to satisfy investigators that they did destroy it. Experts note that old supplies of anthrax would have degraded by now.

While the Bush administration argued before taking the country to war that Iraq's arsenal posed an imminent threat, much of what Kay discovered is that Iraq had interest in such weapons and was researching some agents.

Sen. Joe Lieberman, D-Conn., said Kay's report shows Saddam's clear intent to develop chemical and biological weapons and the missiles to deliver them. He said, however, that the administration didn't tell the public the whole truth.

"There is some evidence that the Bush administration exaggerated unnecessarily," he told "Fox News Sunday." Lieberman, a presidential candidate, said the exaggeration "did discredit what was otherwise a very just cause of fighting tyranny and terrorism."

Bush and Secretary of State Colin Powell have contended the vial of botulinum bacteria that Kay's team found is one strong piece of evidence of Saddam's weapons intent.

Searches have been unsuccessful for the kind of long-range Scud missiles the Iraqis fired at Saudi Arabia and Israel in 1991. Many were destroyed during and after the Persian Gulf War, but the Bush administration had accused Iraq of continuing to hide Scuds.

Kay said there are indications there may still be Scuds even though Iraq declared it got rid of them in the early 1990s.

"We have Iraqis now telling us that they continued until 2001, early 2002, to be capable of mixing and preparing Scud missile fuel. Scud missile fuel is only useful in Scud missiles," he said. "Why would you continue to produce Scud missile fuel if you didn't have Scuds? We're looking for the Scuds."

Kay's report to Congress said the information on fuel production came from Iraqi sources and has not been confirmed with documents or physical evidence.

Weapons hunters still are looking for chemical weapons at scores of large ammunition storage sites throughout Iraq. Because of the size of the depots, searchers have examined only 10 of 130 sites so far, Kay said.

"These are sites that contain -- the best estimate is between 600,000 and 650,000 tons of arms," he said. "That's about one-third of the entire ammunition stockpile of the much larger U.S. military."

The Iraqis stored chemical weapons, often unmarked, among conventional munitions, so "you really have to examine each one," Kay said. He said 26 sites are on a critical list to be examined quickly.