WASHINGTON - One of the key Iraqi defectors who claimed Saddam Hussein had mobile biological warfare facilities -- a claim now questioned by Secretary of State Colin Powell -- is the brother of a top aide to pro-invasion exile leader Ahmed Chalabi, senior officials said.
The defector, code named Curveball, was one of four informers put forward by the Iraqi National Congress, a U.S.-funded group of Iraqi exiles that worked closely with the Bush administration in the run-up to the war. Chalabi led that group in the United States and is now a member of the Iraqi Governing Council in Iraq.
U.S. intelligence officials never directly questioned Curveball before the war, the officials said.
A second defector was determined to be a fabricator, but his claims still found their way into the Bush administration's case for war, according to U.S. officials.
"The other two (defectors) were not as significant," said a senior U.S. official, who like all of those who spoke requested anonymity. "Their information appeared corroborative of the overall thing."
Powell's questioning of the defectors' claims puts added pressure on a bipartisan commission named by President Bush in February to examine the quality and use of pre-war intelligence that Saddam had secret stockpiles of chemical weapons and was developing nuclear weapons in violation of a U.N. ban.
U.S.-led occupation troops and arms inspectors have found no weapons stockpiles or evidence that Iraq had an active nuclear program. Two trailers matching the description of the alleged biowarfare vehicles were turned over to U.S. troops, but their purpose remains in dispute.
In his speech Feb. 5, 2003, to the U.N. Security Council, Powell charged that Iraq had mobile biological warfare production and research facilities. At the time, he was seeking a U.N. resolution backing a U.S.-led invasion.
Returning from a visit to Germany and Belgium, Powell on Friday acknowledged that the information underpinning that charge, which he called "the most dramatic" part of his U.N. presentation, is now in doubt.
"It appears not to be the case that it (the defectors' information) was that solid," he said. "The commission that is going to be starting its work soon I hope will look into these matters to see whether or not the intelligence agency had a basis for the confidence that they placed in the intelligence at that time."
Senior U.S. officials said it was not the CIA but the Defense Intelligence Agency, the top U.S. military intelligence organization, which was responsible for analyzing and corroborating the defectors' information.
The DIA received the defectors' claims through its Information Collection Program, a multimillion-dollar effort to gather intelligence inside Iraq run by the Iraqi National Congress and paid for by U.S. taxpayers.
Curveball stood out as the best placed of the four INC-supplied defectors whose tales formed the basis of the story that Iraq had mobile weapons facilities.
Claiming to be a chemical engineer, he said he had helped design and build such facilities disguised as trucks and railway cars, said the senior U.S. official.
Curveball told his story to German intelligence, which relayed it to the DIA.
"Curveball was the main pillar of the report," one official said.
The defector was eventually determined to be a brother of a top aide to Chalabi, who lobbied for years in Washington for a U.S.-led ouster of Saddam and forged close ties to pro-invasion hawks in the U.S. government.
A DIA spokesman did not return a call for comment.