The FBI is examining whether Pentagon officials who had frequent contacts with Iraqi exile Ahmad Chalabi (search) may have leaked sensitive information that American intelligence had broken Iran's secret communications codes, a law enforcement official said.
Chalabi, a longtime favorite of some in the Pentagon, is at the center of a controversy over whether he then shared with Iranian officials the closely guarded information about methods used by the United States to spy on the Iranian regime.
Government officials said there is evidence that Chalabi or his followers told Iran the United States had cracked some of its codes for transmitting sensitive information.
The officials said the FBI is investigating whether anyone in the U.S. government may have provided Chalabi the information, a potential criminal offense that may have hurt American efforts to monitor Tehran's activities.
The law enforcement official said the Pentagon officials were a logical first place to start, but the investigation wouldn't be limited until the FBI determined how the information was compromised. The government and law enforcement officials spoke only on condition of anonymity, in many cases, because the information is sensitive and part of an ongoing investigation.
The New York Times reported in its Thursday editions that federal investigators have started giving polygraph tests to civilian Pentagon employees in attempt to determine who may have disclosed the highly classified intelligence.
During an on-board news conference with reporters as he flew to Singapore Thursday, Rumsfeld said he did not know whether officials in the Pentagon have been questioned by the FBI in connection with Chalabi.
"The press is reporting that there is an investigation going on. I do not have personal knowledge of that," he said, adding he was not sure whether anyone in the Pentagon had been questioned.
In Najaf, Iraq, Chalabi told The Associated Press that reports saying he leaked the highly classified information are "false" and "stupid."
"Where would I get this from?" Chalabi asked. "I have no such information. How would I know anything about that? That's stupid from every aspect."
In a letter Wednesday to Attorney General John Ashcroft and FBI Director Robert Mueller, two attorneys for Chalabi reiterated his denials, saying he would never endanger U.S. national security. They asked Ashcroft and Mueller to order an investigation into the sources who disclosed the information to the media.
Chalabi's defenders have used the unattributed nature of the alleged leak to Iran to suggest they are part of a baseless smear campaign.
Richard Perle (search), a former Pentagon adviser now with the conservative American Enterprise Institute think tank, said he finds it inconceivable that Iran's top intelligence official in Baghdad would have used a compromised channel to tell Tehran that the United States was reading its communications, as has been reported.
U.S. intelligence reportedly intercepted that message, which indicated Chalabi had provided the information.
"The idea that the Iranians, having been informed that their codes were broken, would then use their broken codes back to Iran is absurd," Perle said. "It is so basic of a mistake. ... It is comparable to a math teacher instructing a student that two and two is five."
Congressional aides said members of the Senate Intelligence Committee received a briefing Wednesday on Chalabi. The aides also spoke on condition of anonymity because the session was classified.
House Intelligence Chairman Porter Goss, R-Fla., said he has never had a great deal of confidence in Chalabi. He wouldn't comment directly on whether his committee was inquiring into Chalabi's actions, but said, "I would say that the oversight has worked well in matters relating to Mr. Chalabi."
The CIA and some in the State Department have been suspicious of Chalabi's information and allegiances for some time. He provided intelligence sources to the Bush administration about weapons of mass destruction, used to justify the U.S. war against Iraq, but his information came under major criticism after no weapons were found.
Chalabi, a member of the hand-picked Iraqi Governing Council, has also been accused of meddling in an investigation into Iraq's oil-for-food program during the regime of former President Saddam Hussein.
Allegations that Chalabi passed highly sensitive information to Iran have lingered for weeks, and some news organizations were asked by U.S. officials not to report the details about the code-breaking because it would endanger an investigation.
Entifadh Qanbar, a spokesman for Chalabi's Iraqi National Congress (search), said the group welcomed any congressional investigations because it had nothing to hide.